Tag Archives: Poland

Science advice conference in Brussels, Belgium, Sept. 29 – 30, 2016 and a call for speakers

This is the second such conference and they are issuing a call for speakers; the first was held in New Zealand in 2014 (my April 8, 2014 post offers an overview of the then proposed science advice conference). Thanks to David Bruggeman and his Feb. 23, 2016 posting (on the Pasco Phronesis blog) for the information about this latest one (Note: A link has been removed),

The International Network for Global Science Advice (INGSA) is holding its second global conference in Brussels this September 29 and 30, in conjunction with the European Commission. The organizers have the following goals for the conference:

Identify core principles and best practices, common to structures providing scientific advice for governments worldwide.

Identify practical ways to improve the interaction of the demand and supply side of scientific advice.

Describe, by means of practical examples, the impact of effective science advisory processes.

Here’s a little more about the conference from its webpage on the INGSA website,

Science and Policy-Making: towards a new dialogue

29th – 30th September 2016, Brussels, Belgium

Call for suggestions for speakers for the parallel sessions

BACKGROUND:

“Science advice has never been in greater demand; nor has it been more contested.”[1] The most complex and sensitive policy issues of our time are those for which the available scientific evidence is ever growing and multi-disciplined, but still has uncertainties. Yet these are the very issues for which scientific input is needed most. In this environment, the usefulness and legitimacy of expertise seems obvious to scientists, but is this view shared by policy-makers?

OBJECTIVES:

A two-day conference will take place in Brussels, Belgium, on Thursday 29th and Friday 30th September 2016. Jointly organised by the European Commission and the International Network for Government Science Advice (INGSA), the conference will bring together users and providers of scientific advice on critical, global issues. Policy-makers, leading practitioners and scholars in the field of science advice to governments, as well as other stakeholders, will explore principles and practices in a variety of current and challenging policy contexts. It will also present the new Scientific Advice Mechanism [SAM] of the European Commission [emphasis mine; I have more about SAM further down in the post] to the international community. Through keynote lectures and plenary discussions and topical parallel sessions, the conference aims to take a major step towards responding to the challenge best articulated by the World Science Forum Declaration of 2015:

“The need to define the principles, processes and application of science advice and to address the theoretical and practical questions regarding the independence, transparency, visibility and accountability of those who receive and provide advice has never been more important. We call for concerted action of scientists and policy-makers to define and promulgate universal principles for developing and communicating science to inform and evaluate policy based on responsibility, integrity, independence, and accountability.”

The conference seeks to:

Identify core principles and best practices, common to structures providing scientific advice for governments worldwide.
Identify practical ways to improve the interaction of the demand and supply side of scientific advice.
Describe, by means of practical examples, the impact of effective science advisory processes.

The Programme Committee comprises:

Eva Alisic, Co-Chair of the Global Young Academy

Tateo Arimoto, Director of Science, Technology and Innovation Programme; The Japanese National Graduate Institute for Policy Studies

Peter Gluckman, Chair of INGSA and Prime Minister’s Chief Science Advisor, New Zealand (co-chair)

Robin Grimes, UK Foreign Office Chief Scientific Adviser

Heide Hackmann, International Council for Science (ICSU)

Theodoros Karapiperis, European Parliament – Head of Scientific Foresight Unit (STOA), European Parliamentary Research Service (EPRS) – Science and Technology Options Assessment Panel

Johannes Klumpers, European Commission, Head of Unit – Scientific Advice Mechanism (SAM) (co-chair)

Martin Kowarsch, Head of the Working Group Scientific assessments, Ethics and Public Policy, Mercator Research Institute on Global Commons and Climate Change

David Mair, European Commission – Joint Research Centre (JRC)

Rémi Quirion, Chief Scientist, Province of Québec, Canada

Flavia Schlegel, UNESCO Assistant Director-General for the Natural Sciences

Henrik Wegener, Executive Vice President, Chief Academic Officer, Provost at Technical University of Denmark, Chair of the EU High Level Group of Scientific Advisors

James Wilsdon, Chair of INGSA, Professor of Research Policy, Director of Impact & Engagement, University of Sheffield
Format

The conference will be a combination of plenary lectures and topical panels in parallel (concurrent) sessions outlined below. Each session will include three speakers (15 minute address with 5 minute Q & A each) plus a 30 minute moderated discussion.

Parallel Session I: Scientific advice for global policy

The pathways of science advice are a product of a country’s own cultural history and will necessarily differ across jurisdictions. Yet, there is an increasing number of global issues that require science advice. Can scientific advice help to address issues requiring action at international level? What are the considerations for providing science advice in these contexts? What are the examples from which we can learn what works and what does not work in informing policy-making through scientific advice?

Topics to be addressed include:

Climate Change – Science for the Paris Agreement: Did it work?
Migration: How can science advice help?
Zika fever, dementia, obesity etc.; how can science advice help policy to address the global health challenges?

Parallel Session II: Getting equipped – developing the practice of providing scientific advice for policy

The practice of science advice to public policy requires a new set of skills that are neither strictly scientific nor policy-oriented, but a hybrid of both. Negotiating the interface between science and policy requires translational and navigational skills that are often not acquired through formal training and education. What are the considerations in developing these unique capacities, both in general and for particular contexts? In order to be best prepared for informing policy-making, up-coming needs for scientific advice should ideally be anticipated. Apart from scientific evidence sensu stricto, can other sources such as the arts, humanities, foresight and horizon scanning provide useful insights for scientific advice? How can scientific advice make best use of such tools and methods?

Topics to be addressed include:

How to close the gap between the need and the capacity for science advice in developing countries with limited or emerging science systems?
What skills do scientists and policymakers need for a better dialogue?
Foresight and science advice: can foresight and horizon scanning help inform the policy agenda?

Parallel Session III: Scientific advice for and with society

In many ways, the practice of science advice has become a key pillar in what has been called the ‘new social contract for science[2]’. Science advice translates knowledge, making it relevant to society through both better informed policy and by helping communities and their elected representatives to make better informed decisions about the impacts of technology. Yet providing science advice is often a distributed and disconnected practice in which academies, formal advisors, journalists, stakeholder organisations and individual scientists play an important role. The resulting mix of information can be complex and even contradictory, particularly as advocate voices and social media join the open discourse. What considerations are there in an increasingly open practice of science advice?

Topics to be addressed include:

Science advice and the media: Lost in translation?
Beyond the ivory tower: How can academies best contribute to science advice for policy?
What is the role of other stakeholders in science advice?

Parallel Session IV: Science advice crossing borders

Science advisors and advisory mechanisms are called upon not just for nationally-relevant advice, but also for issues that increasingly cross borders. In this, the importance of international alignment and collaborative possibilities may be obvious, but there may be inherent tensions. In addition, there may be legal and administrative obstacles to transnational scientific advice. What are these hurdles and how can they be overcome? To what extent are science advisory systems also necessarily diplomatic and what are the implications of this in practice?

Topics to be addressed include:

How is science advice applied across national boundaries in practice?
What support do policymakers need from science advice to implement the Sustainable Development Goals in their countries?
Science Diplomacy/Can Scientists extend the reach of diplomats?

Call for Speakers

The European Commission and INGSA are now in the process of identifying speakers for the above conference sessions. As part of this process we invite those interested in speaking to submit their ideas. Interested policy-makers, scientists and scholars in the field of scientific advice, as well as business and civil-society stakeholders are warmly encouraged to submit proposals. Alternatively, you may propose an appropriate speaker.

The conference webpage includes a form should you wish to submit yourself or someone else as a speaker.

New Scientific Advice Mechanism of the European Commission

For anyone unfamiliar with the Scientific Advice Mechanism (SAM) mentioned in the conference’s notes, once Anne Glover’s, chief science adviser for the European Commission (EC), term of office was completed in 2014 the EC president, Jean-Claude Juncker, obliterated the position. Glover, the first and only science adviser for the EC, was to replaced by an advisory council and a new science advice mechanism.

David Bruggemen describes the then situation in a May 14, 2015 posting (Note: A link has been removed),

Earlier this week European Commission President Juncker met with several scientists along with Commission Vice President for Jobs, Growth, Investment and Competitiveness [Jyrki] Katainen and the Commissioner for Research, Science and Innovation ]Carlos] Moedas. …

What details are publicly available are currently limited to this slide deck. It lists two main mechanisms for science advice, a high-level group of eminent scientists (numbering seven), staffing and resource support from the Commission, and a structured relationship with the science academies of EU member states. The deck gives a deadline of this fall for the high-level group to be identified and stood up.

…

… The Commission may use this high-level group more as a conduit than a source for policy advice. A reasonable question to ask is whether or not the high-level group can meet the Commission’s expectations, and those of the scientific community with which it is expected to work.

David updated the information in a January 29,2016 posting (Note: Links have been removed),

Today the High Level Group of the newly constituted Scientific Advice Mechanism (SAM) of the European Union held its first meeting. The seven members of the group met with Commissioner for Research, Science and Innovation Carlos Moedas and Andrus Ansip, the Commission’s Vice-President with responsibility for the Digital Single Market (a Commission initiative focused on making a Europe-wide digital market and improving support and infrastructure for digital networks and services).

Given it’s early days, there’s little more to discuss than the membership of this advisory committee (from the SAM High Level Group webpage),

Janusz Bujnicki

Professor, Head of the Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw

Professor of Biology, and head of a research group at IIMCB in Warsaw and at Adam Mickiewicz University, Poznań, Poland. Janusz Bujnicki graduated from the Faculty of Biology, University of Warsaw in 1998, defended his PhD in 2001, was awarded with habilitation in 2005 and with the professor title in 2009.

Bujnicki’s research combines bioinformatics, structural biology and synthetic biology. His scientific achievements include the development of methods for computational modeling of protein and RNA 3D structures, discovery and characterization of enzymes involved in RNA metabolism, and engineering of proteins with new functions. He is an author of more than 290 publications, which have been cited by other researchers more than 5400 times (as of October 2015). Bujnicki received numerous awards, prizes, fellowships, and grants including EMBO/HHMI Young Investigator Programme award, ERC Starting Grant, award of the Polish Ministry of Science and award of the Polish Prime Minister, and was decorated with the Knight’s Cross of the Order of Polonia Restituta by the President of the Republic of Poland. In 2013 he won the national plebiscite “Poles with Verve” in the Science category.

Bujnicki has been involved in various scientific organizations and advisory bodies, including the Polish Young Academy, civic movement Citizens of Science, Life, Environmental and Geo Sciences panel of the Science Europe organization, and Scientific Policy Committee – an advisory body of the Ministry of Science and Higher Education in Poland. He is also an executive editor of the scientific journal Nucleic Acids Research.

Curriculum vitae 206 KB

Pearl Dykstra

Professor of Sociology, Erasmus University Rotterdam

Professor Dykstra has a chair in Empirical Sociology and is Director of Research of the Department of Public Administration and Sociology at the Erasmus University Rotterdam. Previously, she had a chair in Kinship Demography at Utrecht University (2002-2009) and was a senior scientist at the Netherlands Interdisciplinary Demographic Institute (NIDI) in The Hague (1990-2009).

Her publications focus on intergenerational solidarity, aging societies, family change, aging and the life course, and late-life well-being. She is an elected member of the Netherlands Royal Academy of Arts and Sciences (KNAW, 2004) and Vice-President of the KNAW as of 2011, elected Member of the Dutch Social Sciences Council (SWR, 2006), and elected Fellow of the Gerontological Society of America (2010). In 2012 she received an ERC Advanced Investigator Grant for the research project “Families in context”, which will focus on the ways in which policy, economic, and cultural contexts structure interdependence in families.

Curriculum vitae 391 KB

Elvira Fortunato

Deputy Chair

Professor, Materials Science Department of the Faculty of Science and Technology, NOVA University, Lisbon

Professor Fortunato is a full professor in the Materials Science Department of the Faculty of Science and Technology of the New University of Lisbon, a Fellow of the Portuguese Engineering Academy since 2009 and decorated as a Grand Officer of the Order of Prince Henry the Navigator by the President of the Republic in 2010, due to her scientific achievements worldwide. In 2015 she was appointed by the Portuguese President Chairman of the Organizing Committee of the Celebrations of the National Day of Portugal, Camões and the Portuguese Communities.

She was also a member of the Portuguese National Scientific & Technological Council between 2012 and 2015 and a member of the advisory board of DG CONNECT (2014-15).

Currently she is the director of the Institute of Nanomaterials, Nanofabrication and Nanomodeling and of CENIMAT. She is member of the board of trustees of Luso-American Foundation (Portugal/USA, 2013-2020).

Fortunato pioneered European research on transparent electronics, namely thin-film transistors based on oxide semiconductors, demonstrating that oxide materials can be used as true semiconductors. In 2008, she received in the 1st ERC edition an Advanced Grant for the project “Invisible”, considered a success story. In the same year she demonstrated with her colleagues the possibility to make the first paper transistor, starting a new field in the area of paper electronics.

Fortunato published over 500 papers and during the last 10 years received more than 16 International prizes and distinctions for her work (e.g: IDTechEx USA 2009 (paper transistor); European Woman Innovation prize, Finland 2011).

Curriculum vitae 339 KB

Rolf-Dieter Heuer

Director-General of the European Organization for Nuclear Research (CERN)

Professor Heuer is an experimental particle physicist and has been CERN Director-General since January 2009. His mandate, ending December 2015, is characterised by the start of the Large Hadron Collider (LHC) 2009 as well as its energy increase 2015, the discovery of the H-Boson and the geographical enlargement of CERN Membership. He also actively engaged CERN in promoting the importance of science and STEM education for the sustainable development of the society. From 2004 to 2008, Prof. Heuer was research director for particle and astroparticle physics at the DESY laboratory, Germany where he oriented the particle physics groups towards LHC by joining both large experiments, ATLAS and CMS. He has initiated restructuring and focusing of German high energy physics at the energy frontier with particular emphasis on LHC (Helmholtz Alliance “Physics at the Terascale”). In April 2016 he will become President of the German Physical Society. He is designated President of the Council of SESAME (Synchrotron-Light for Experimental Science and Applications in the Middle East).

Prof. Heuer has published over 500 scientific papers and holds many Honorary Degrees from universities in Europe, Asia, Australia and Canada. He is Member of several Academies of Sciences in Europe, in particular of the German Academy of Sciences Leopoldina, and Honorary Member of the European Physical Society. In 2015 he received the Grand Cross 1st class of the Order of Merit of the Federal Republic of Germany.

Curriculum vitae

Julia Slingo

Chief Scientist, Met Office, Exeter

Dame Julia Slingo became Met Office Chief Scientist in February 2009 where she leads a team of over 500 scientists working on a very broad portfolio of research that underpins weather forecasting, climate prediction and climate change projections. During her time as Chief Scientist she has fostered much stronger scientific partnerships across UK academia and international research organisations, recognising the multi-disciplinary and grand challenge nature of weather and climate science and services. She works closely with UK Government Chief Scientific Advisors and is regularly called to give evidence on weather and climate related issues.

Before joining the Met Office she was the Director of Climate Research in NERC’s National Centre for Atmospheric Science, at the University of Reading. In 2006 she founded the Walker Institute for Climate System Research at Reading, aimed at addressing the cross disciplinary challenges of climate change and its impacts. Julia has had a long-term career in atmospheric physics, climate modelling and tropical climate variability, working at the Met Office, ECMWF and NCAR in the USA.

Dame Julia has published over 100 peer reviewed papers and has received numerous awards including the prestigious IMO Prize of the World Meteorological Organization for her outstanding work in meteorology, climatology, hydrology and related sciences. She is a Fellow of the Royal Society, an Honorary Fellow of the Royal Society of Chemistry and an Honorary Fellow of the Institute of Physics.

Curriculum vitae 239 KB

Cédric Villani

Director, Henri Poincaré Institute, Paris

Born in 1973 in France, Cédric Villani is a mathematician, director of the Institut Henri Poincaré in Paris (from 2009), and professor at the Université Claude Bernard of Lyon (from 2010). In December 2013 he was elected to the French Academy of Sciences.

He has worked on the theory of partial differential equations involved in statistical mechanics, specifically the Boltzmann equation, and on nonlinear Landau damping. He was awarded the Fields Medal in 2010 for his works.

Since then he has been playing an informal role of ambassador for the French mathematical community to media (press, radio, television) and society in general. His books for non-specialists, in particular Théorème vivant (2012, translated in a dozen of languages), La Maison des mathématiques (2014, with J.-Ph. Uzan and V. Moncorgé) and Les Rêveurs lunaires (2015, with E. Baudoin) have all found a wide audience. He has also given hundreds of lectures for all kinds of audiences around the world.

He participates actively in the administration of science, through the Institut Henri Poincaré, but also by sitting in a number of panels and committees, including the higher council of research and the strategic council of Paris. Since 2010 he has been involved in fostering mathematics in Africa, through programs by the Next Einstein Initiative and the World Bank.

Believing in the commitment of scientists in society, Villani is also President of the Association Musaïques, a European federalist and a father of two.

Website

Henrik C. Wegener

Chair

Executive Vice President, Chief Academic Officer and Provost, Technical University of Denmark

Henrik C. Wegener is Executive Vice President and Chief Academic Officer at Technical University of Denmark since 2011. He received his M.Sc. in food science and technology at the University of Copenhagen in 1988, his Ph.D. in microbiology at University of Copenhagen in 1992, and his Master in Public Administration (MPA) form Copenhagen Business School in 2005.

Henrik C. Wegener was director of the National Food Institute, DTU from 2006-2011 and before that head of the Department of Epidemiology and Risk Assessment at National Food and Veterinary Research Institute, Denmark (2004-2006). From 1994-1999, he was director of the Danish Zoonosis Centre, and from 1999-2004 professor of zoonosis epidemiology at Danish Veterinary Institute. He was stationed at World Health Organization headquarters in Geneva from 1999-2000. With more than 3.700 citations (h-index 34), he is the author of over 150 scientific papers in journals, research monographs and proceedings, on food safety, zoonoses, antimicrobial resistance and emerging infectious diseases.

He has served as advisor and reviewer to national and international authorities & governments, international organizations and private companies, universities and research foundations, and he has served, and is presently serving, on several national and international committees and boards on food safety, veterinary public health and research policy.

Henrik C. Wegener has received several awards, including the Alliance for the Prudent Use of Antibiotics International Leadership Award in 2003.

That’s quite a mix of sciences and I’m happy to see a social scientist has been included.

Conference submissions

Getting back to the conference and its call for speakers, the deadline for submissions is March 25, 2016. Interestingly, there’s also this (from conference webpage),

The deadline for submissions is 25^th March 2016. The conference programme committee with session chairs will review all proposals and select those that best fit the aim of each session while also representing a diverse range of perspectives. We aim to inform selected speakers within 4 weeks of the deadline to enable travel planning to Brussels.

To make the conference as accessible as possible, there is no registration fee. [emphasis mine] The European Commission will cover travel accommodation costs only for confirmed speakers for whom the travel and accommodation arrangements will be made by the Commission itself, on the basis of the speakers’ indication.

Good luck!

*Head for conference submissions added on Feb. 29, 2016 at 1155 hundred hours.

Back to the mortar and pestle for perovskite-based photovoltaics

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This mechanochemistry (think mortar and pestle) story about perovskite comes from Poland. From a Jan. 14, 2016 Institute of Physical Chemistry of the Polish Academy of Sciences press release (also on EurekAlert but dated Jan. 16, 2016),

Perovskites, substances that perfectly absorb light, are the future of solar energy. The opportunity for their rapid dissemination has just increased thanks to a cheap and environmentally safe method of production of these materials, developed by chemists from Warsaw, Poland. Rather than in solutions at a high temperature, perovskites can now be synthesized by solid-state mechanochemical processes: by grinding powders.

We associate the milling of chemicals less often with progress than with old-fashioned pharmacies and their inherent attributes: the pestle and mortar. [emphasis mine] It’s time to change this! Recent research findings show that by the use of mechanical force, effective chemical transformations take place in solid state. Mechanochemical reactions have been under investigation for many years by the teams of Prof. Janusz Lewinski from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) and the Faculty of Chemistry of Warsaw University of Technology. In their latest publication, the Warsaw researchers describe a surprisingly simple and effective method of obtaining perovskites – futuristic photovoltaic materials with a spatially complex crystal structure.

“With the aid of mechanochemistry we are able to synthesize a variety of hybrid inorganic-organic functional materials with a potentially great significance for the energy sector. Our youngest ‘offspring’ are high quality perovskites. These compounds can be used to produce thin light-sensitive layers for high efficiency solar cells,” says Prof. Lewinski.

Perovskites are a large group of materials, characterized by a defined spatial crystalline structure. In nature, the perovskite naturally occurring as a mineral is calcium titanium(IV) oxide CaTiO3. Here the calcium atoms are arranged in the corners of the cube, in the middle of each wall there is an oxygen atom and at the centre of the cube lies a titanium atom. In other types of perovskite the same crystalline structure can be constructed of various organic and inorganic compounds, which means titanium can be replaced by, for example, lead, tin or germanium. As a result, the properties of the perovskite can be adjusted so as to best fit the specific application, for example, in photovoltaics or catalysis, but also in the construction of superconducting electromagnets, high voltage transformers, magnetic refrigerators, magnetic field sensors, or RAM memories.

At first glance, the method of production of perovskites using mechanical force, developed at the IPC PAS, looks a little like magic.

“Two powders are poured into the ball mill: a white one, methylammonium iodide CH3NH3I, and a yellow one, lead iodide PbI2. After several minutes of milling no trace is left of the substrates. Inside the mill there is only a homogeneous black powder: the perovskite CH3NH3PbI3,” explains doctoral student Anna Maria Cieslak (IPC PAS).

“Hour after hour of waiting for the reaction product? Solvents? High temperatures? In our method, all this turns out to be unnecessary! We produce chemical compounds by reactions occurring only in solids at room temperature,” stresses Dr. Daniel Prochowicz (IPC PAS).

The mechanochemically manufactured perovskites were sent to the team of Prof. Michael Graetzel from the Ecole Polytechnique de Lausanne in Switzerland, where they were used to build a new laboratory solar cell. The performance of the cell containing the perovskite with a mechanochemical pedigree proved to be more than 10% greater than a cell’s performance with the same construction, but containing an analogous perovskite obtained by the traditional method, involving solvents.

“The mechanochemical method of synthesis of perovskites is the most environmentally friendly method of producing this class of materials. Simple, efficient and fast, it is ideal for industrial applications. With full responsibility we can state: perovskites are the materials of the future, and mechanochemistry is the future of perovskites,” concludes Prof. Lewinski.

The described research will be developed within GOTSolar collaborative project funded by the European Commission under the Horizon 2020 Future and Emerging Technologies action.

Perovskites are not the only group of three-dimensional materials that has been produced mechanochemically by Prof. Lewinski’s team. In a recent publication the Warsaw researchers showed that by using the milling technique they can also synthesize inorganic-organic microporous MOF (Metal-Organic Framework) materials. The free space inside these materials is the perfect place to store different chemicals, including hydrogen.

This research was published back in August 2015,

Mechanosynthesis of the hybrid perovskite CH3NH3PbI3: characterization and the corresponding solar cell efficiency by D. Prochowicz, M. Franckevičius, A. M. Cieślak, S. M. Zakeeruddin, M. Grätzel and J. Lewiński. J. Mater. Chem. A, 2015,3, 20772-20777 DOI: 10.1039/C5TA04904K First published online 27 Aug 2015

This paper is behind a paywall.

Zebras, Turing patterns, and the Polish Academy of Sciences

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A Feb. 6, 2015 news item on Azonano profiles some research from the Polish Academy of Sciences’ Institute of Physical Chemistry (IPC PAS),

In the world of single atoms and molecules governed by chaotic fluctuations, is the spontaneous formation of Turing patterns possible – the same ones that are responsible for the irregular yet periodic shapes of the stripes on zebras’ bodies? A Polish-Danish team of physicists has for the first time demonstrated that such a process can not only occur, but can also be used for potentially very interesting applications.

A Feb. 6, 2015 IPC PAS press release (also on EurekAlert), which originated the news item, describes Turing’s patterns and the research in more detail,

Everyone is familiar with a zebra’s stripes, but not everyone knows that these are the manifestations of chemical reactions taking place according to a process first described by the famous British mathematician Alan Turing, the creator of the basics of today’s computer science. Turing patterns, most commonly displayed in chemistry as periodic changes in the concentration of chemical substances, have hitherto only been observed in dimensions of microns or larger. It seemed that on a smaller scale – at the nanoscale, where random fluctuations rule the movement of single atoms and molecules – these patterns do not have the right to form spontaneously.

“So far, no-one has even studied the possibility of the formation of Turing patterns by single atoms or molecules. However, our results show that Turing nanostructures may exist. And since this is the case, we will be able to find very specific applications for them in nanotechnology and materials science,” says Dr. Bogdan Nowakowski from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, one of the physicists in the Polish-Danish team that has recently conducted computer simulations and theoretical analyses on Turing nanostructures.

Turing patterns occur in dynamic systems far from a state of equilibrium. Under the appropriate conditions there may then be a feedback mechanism: chemical reactions taking place may influence the concentration of their own components, which in turn may change the course of the reaction itself. The process leads to the formation of periodic, but not necessarily monotonously regular patterns. In nature, these patterns play an important role, particularly in the formation of young organisms (morphogenesis). For example, in the initial phases of the development of vertebrate embryos, this is how periodic segments, somites, are formed in the dorsal mesoderm, which are later converted into, among others, vertebrae, components of the spine.

“In our studies we considered very simple reactions of two model substances with different rates of diffusion. Computer simulations carried out using molecular dynamics, in collaboration with Dr. Jesper Hansen from the Danish University of Roskilde, gave rise to a very interesting picture,” says Dr. Piotr Dziekan (IPC PAS).

Clear and permanent patterns formed spontaneously in the simulated systems (of nanometer dimensions) – periodic changes in the density of molecules, which remained stable despite the destructive influence of fluctuations. It turned out that one cycle of concentration changes within the Turing pattern could appear on a length of just 20 molecules.

For Turing nanostructures to be formed, chemical reactions satisfying certain conditions have to take place between the chemical substances. This requirement severely reduces the number of compounds that can participate in the process and, consequently, severely limits the potential applications. However, the simulations carried out by the Polish-Danish team suggest that Turing nanostructures can quite easily be transferred to other compounds, not participating directly in the main reaction.

“Turing nanostructures can only arise with carefully selected chemical substances. Fortunately, the pattern formed by them can be ‘imprinted’ in the concentration of other chemical compounds. For the pattern to be copied, these compounds must fulfill only two simple conditions: they must bind to one of the reactants of the main reaction and diffuse slowly,” explains Dr. Dziekan.

This work is theoretical as the final paragraph of the press release intimates,

The possibility of forming Turing patterns on nanometer distances opens the door to interesting applications, particularly in the field of surface modification of materials. By skillfully selecting the chemical composition of the reagents and the conditions in which the reaction occurs, it could be possible to form Turing patterns in two dimensions (on the same surface of the material), or three (also in the space adjacent to the surface). The formed patterns could then be fixed, e.g. by photopolymerisation, thereby obtaining a permanent, stable, extended surface with a complex, periodic structure.

Here’s a link to and a citation for the paper,

Nanoscale Turing structures by Piotr Dziekan. J. S. Hansen, and Bogdan Nowakowski. J. Chem. Phys. 141, 124106 (2014); http://dx.doi.org/10.1063/1.4895907

This paper is behind a paywall.

Martini with your salad? an update on Janus particles and emulsification

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Close to a year since I first posted about this research (my July 8, 2013 posting about oil, electricity, and emulsification), scientists have published their latest work on using electricity to control nanoparticles. A June 26, 2014 Polish Academy of Sciences press release (also on EurekAlert) provides this summary,

Everything depends on how you look at them. Looking from one side you will see one face; and when looking from the opposite side – you will see a different one. So appear Janus capsules, miniature, hollow structures, in different fragments composed of different micro- and nanoparticles. Theoreticians were able to design models of such capsules, but a real challenge was to produce them. Now, Janus capsules can be produced easily and at low cost.

Before describing the process for producing Janus capsules, an explanation of Janus (a Roman god) and the problem the scientists were trying to solve (from the press release),

Janus, the old Roman god of beginnings and transitions, attracted believers’ attention with his two faces, each looking to different direction of the world. Janus capsules – ‘bubbles’ made up of two shells stuck one another, each composed of micro- or nanoparticles of different properties – have been for some time attracting the researchers’ attention. They see in the capsules an excellent tool for transporting drugs and a vehicle leading to innovative materials. To have, however, Janus capsules generally accessible, efficient methods for their mass production must be developed. An important step in this direction is the achievement of researchers from the Norwegian and French research institutions and the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, reported recently in one of the most reputable scientific journals: “Nature Communications”.

At present, it is not a problem to produce Janus spheres – round, entirely filled micro- and nanoobjects with one part having different properties than the other. Such spheres can be, for instance, produced by sticking together two drops of different substances. After merging, the new drop requires a sufficiently fast fixation only, e.g., by cooling it down or initiating polymerisation of its materials. For instance, Janus spheres are particles with white and black halves, used for image generation in electrophoretic displays incorporated in e-book reading devices.

“Janus capsules differ from Janus spheres: the former are hollow structures, and their partially permeable shell is made of colloidal particles. How to make such a ‘two-faced bubble’ using micro- and nanoparticles? Many researchers reflect on the problem. We proposed a really not complicated solution”, says Dr Zbigniew Rozynek (IPC PAS [Institute of Physical Chemistry Polish Academy of Sciences]), who experimentally studied Janus capsules during his postdoctoral training at Norwegian University of Science and Technology in Trondheim.

Here’s an illustration the researchers have provided,

Caption: These are typical capsules (mainly Janus capsules) obtained with the method described in the press release of the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw.
Credit: adopted from Nat. Commun. 5, 3945 (2014)

Here’s how the researchers solved their problem (from the press release),

In their experiments, an international team of researchers produced Janus capsules with drops of single millilitres in volume. The drops were coated, for instance, with polystyrene or glass nanoparticles with diameters of about 500 nm (billionth parts of a meter) or 1000 nm, respectively. Also differently coloured polyethylene particles were used.

The experiments were performed with oil drops suspended in another oil. To a so prepared environment micro- or nanoparticles of one type were placed and deposited on the surface of a selected drop. Then, particles of another type were brought to the surface of the second drop. Due to the action of capillary forces, the particles were durably kept on the surfaces of both drops, being approximately uniformly distributed.

When an external electric field was turned on, microflows were induced inside and outside the drops. The microflows transported the particles toward the electric ‘equator’. In this step, the packing of colloidal particles could be controlled by shaking the drops in a slowly alternating electric field. The way how the particles are packed is an important factor, as it determines the number and size of pores of the future capsule, and consequently the capsule permeability.

The microflows around the electric equators of the drops resulted in formation of a ring-shaped ribbon, composed of densely packed particles , whereas both electric ‘poles’ became particles-free regions. At the same time, the poles of each drop were acquiring opposite electric charges.

Opposite electric charges attract one another, so the drops with charged poles were heading to each other. In this step, the only thing to do was to convince both drops not only to adjoin with their poles, but actually to merge. For that purpose the long-known electrocoalescence was used: the drops were stimulated for faster merging by an electric field. Finally the drops electrocoalesced, resulting in the formation of a Janus capsule. Due to a dense packing of particles within the capsule the particles of different types virtually did not mix with each other.

“It’s like the famous James Bond’s martini: it was always to be shaken, not stirred“, laughs Dr Rozynek. [emphasis mine]

The ultimate capsule appearance was determined by the number of particles deposited on the surfaces of initial drops. If the particles covered both drops with a uniform film, extending almost to the poles, the coalescence resulted in a non-spherical structure. When empty areas around the poles were suitably larger, the Janus capsules acquired a spherical shape. Finally, if the ribbons around the equators of the initial drops were narrow, the coalescence resulted in formation of a structure, which could be called a Janus ring.

The rings with two parts composed of two different types of particles provide interesting opportunities. They can be further stuck each other and produce more complex striped structures. The capsules could be then composed of alternately placed strips of particles, with each strip having different properties than its neighbours.

Janus capsules enable encapsulation of microobjects, nanoparticles or molecules, which must be protected against the environment because of their sensitivity or reactivity. Different properties of both capsule parts make it easier to control the movement of the capsules and the release of their contents. In view of these factors, Janus capsules may find numerous applications. The proposed method for producing the Janus capsules is potentially of great importance for pharmaceutical, dye or food industries, as well as for the development of materials engineering and medicine.

Here’s a link to and a citation for the paper,

Electroformation of Janus and patchy capsules by Zbigniew Rozynek, Alexander Mikkelsen, Paul Dommersnes, & Jon Otto Fossum. Nature Communications 5, Article number: 3945 doi:10.1038/ncomms4945 Published 23 May 2014

This is an open access paper,

Canada’s ‘nano’satellites to gaze upon luminous stars

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The launch (from Yasny, Russia) of two car battery-sized satellites happened on June 18, 2014 at 15:11:11 Eastern Daylight Time according to a June 18, 2014 University of Montreal (Université de Montréal) news release (also on EurekAlert).

Together, the satellites are known as the BRITE-Constellation, standing for BRIght Target Explorer. “BRITE-Constellation will monitor for long stretches of time the brightness and colour variations of most of the brightest stars visible to the eye in the night sky. These stars include some of the most massive and luminous stars in the Galaxy, many of which are precursors to supernova explosions. This project will contribute to unprecedented advances in our understanding of such stars and the life cycles of the current and future generations of stars,” said Professor Moffat [Anthony Moffat, of the University of Montreal and the Centre for Research in Astrophysics of Quebec], who is the scientific mission lead for the Canadian contribution to BRITE and current chair of the international executive science team.

Here’s what the satellites (BRITE-Constellatio) are looking for (from the news release),

Luminous stars dominate the ecology of the Universe. “During their relatively brief lives, massive luminous stars gradually eject enriched gas into the interstellar medium, adding heavy elements critical to the formation of future stars, terrestrial planets and organics. In their spectacular deaths as supernova explosions, massive stars violently inject even more crucial ingredients into the mix. The first generation of massive stars in the history of the Universe may have laid the imprint for all future stellar history,” Moffat explained. “Yet, massive stars – rapidly spinning and with radiation fields whose pressure resists gravity itself – are arguably the least understood, despite being the brightest members of the familiar constellations of the night sky.” Other less-massive stars, including stars similar to our own Sun, also contribute to the ecology of the Universe, but only at the end of their lives, when they brighten by factors of a thousand and shed off their tenuous outer layers.

BRITE-Constellation is both a multinational effort and a Canadian bi-provincial effort,

BRITE-Constellation is in fact a multinational effort that relies on pioneering Canadian space technology and a partnership with Austrian and Polish space researchers – the three countries act as equal partners. Canada’s participation was made possible thanks to an investment of $4.07 million by the Canadian Space Agency. The two new Canadian satellites are joining two Austrian satellites and a Polish satellite already in orbit; the final Polish satellite will be launched in August [2014?].

All six satellites were designed by the University of Toronto Institute for Aerospace Studies – Space Flight Laboratory, who also built the Canadian pair. The satellites were in fact named “BRITE Toronto” and “BRITE Montreal” after the University of Toronto and the University of Montreal, who play a major role in the mission. “BRITE-Constellation will exploit and enhance recent Canadian advances in precise attitude control that have opened up for space science the domain of very low cost, miniature spacecraft, allowing a scientific return that otherwise would have had price tags 10 to 100 times higher,” Moffat said. “This will actually be the first network of satellites devoted to a fundamental problem in astrophysics.”

Is it my imagination or is there a lot more Canada/Canadian being included in news releases from the academic community these days? In fact, I made a similar comment in my June 10, 2014 posting about TRIUMF, Canada’s National Laboratory for Particle and Nuclear Physics where I noted we might not need to honk our own horns quite so loudly.

One final comment, ‘nano’satellites have been launched before as per my Aug. 6, 2012 posting,

The nanosatellites referred to in the Aug.2, 2012 news release on EurekALert aren’t strictly speaking nano since they are measured in inches and weigh approximately eight pounds. I guess by comparison with a standard-sized satellite, CINEMA, one of 11 CubeSats, seems nano-sized. From the news release,

Eleven tiny satellites called CubeSats will accompany a spy satellite into Earth orbit on Friday, Aug. 3, inaugurating a new type of inexpensive, modular nanosatellite designed to piggyback aboard other NASA missions. [emphasis mine]

One of the 11 will be CINEMA (CubeSat for Ions, Neutrals, Electrons, & MAgnetic fields), an 8-pound, shoebox-sized package which was built over a period of three years by 45 students from the University of California, Berkeley, Kyung Hee University in Korea, Imperial College London, Inter-American University of Puerto Rico, and University of Puerto Rico, Mayaguez.

This 2012 project had a very different focus from this Austrian-Canadian-Polish effort. From the University of Montreal news release,

The nanosatellites will be able to explore a wide range of astrophysical questions. “The constellation could detect exoplanetary transits around other stars, putting our own planetary system in context, or the pulsations of red giants, which will enable us to test and refine our models regarding the eventual fate of our Sun,” Moffatt explained.

Good luck!

Italians and Polish collaborate on nanoscale study of vanishing Da Vinci self-portrait

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In addition to a new nondamaging technique to examine paintings (my June 2, 2014 post: Damage-free art authentication and spatially offset Raman spectroscopy [SORS]), there’s a new report in a June 3, 2014 news item on ScienceDaily about a nondamaging technique to examine paper such as the paper on which holds a Da Vinci self-portrait,

One of Leonardo da Vinci’s masterpieces, drawn in red chalk on paper during the early 1500s and widely believed to be a self-portrait, is in extremely poor condition. Centuries of exposure to humid storage conditions or a closed environment has led to widespread and localized yellowing and browning of the paper, which is reducing the contrast between the colors of chalk and paper and substantially diminishing the visibility of the drawing.

A group of researchers from Italy and Poland with expertise in paper degradation mechanisms was tasked with determining whether the degradation process has now slowed with appropriate conservation conditions — or if the aging process is continuing at an unacceptable rate.

Caption: This is Leonardo da Vinci’s self-portrait as acquired during diagnostic studies carried out at the Central Institute for the Restoration of Archival and Library Heritage in Rome, Italy.
Credit: M. C. Misiti/Central Institute for the Restoration of Archival and Library Heritage, Rome

The June 3, 2014 American Institute of Physics news release on EurekAlert provides more detail about the work,

… the team developed an approach to nondestructively identify and quantify the concentration of light-absorbing molecules known as chromophores in ancient paper, the culprit behind the “yellowing” of the cellulose within ancient documents and works of art.

“During the centuries, the combined actions of light, heat, moisture, metallic and acidic impurities, and pollutant gases modify the white color of ancient paper’s main component: cellulose,” explained Joanna Łojewska, a professor in the Department of Chemistry at Jagiellonian University in Krakow, Poland. “This phenomenon is known as ‘yellowing,’ which causes severe damage and negatively affects the aesthetic enjoyment of ancient art works on paper.”

Chromophores are the key to understanding the visual degradation process because they are among the chemical products developed by oxidation during aging and are, ultimately, behind the “yellowing” within cellulose. Yellowing occurs when “chromophores within cellulose absorb the violet and blue range of visible light and largely scatter the yellow and red portions — resulting in the characteristic yellow-brown hue,” said Olivia Pulci, a professor in the Physics Department at the University of Rome Tor Vergata.

To determine the degradation rate of Leonardo’s self-portrait, the team created a nondestructive approach that centers on identifying and quantifying the concentration of chromophores within paper. It involves using a reflectance spectroscopy setup to obtain optical reflectance spectra of paper samples in the near-infrared, visible, and near-ultraviolet wavelength ranges.

Once reflectance data is gathered, the optical absorption spectrum of cellulose fibers that form the sheet of paper can be calculated using special spectroscopic data analysis.

Then, computational simulations based on quantum mechanics — in particular, Time-Dependent Density Functional Theory, which plays a key role in studying optical properties in theoretical condensed matter physics — are tapped to calculate the optical absorption spectrum of chromophores in cellulose.

“Using our approach, we were able to evaluate the state of degradation of Leonardo da Vinci’s self-portrait and other paper specimens from ancient books dating from the 15th century,” said Adriano Mosca Conte, a researcher at the University of Rome Tor Vergata. “By comparing the results of ancient papers with those of artificially aged samples, we gained significant insights into the environmental conditions in which Leonardo da Vinci’s self-portrait was stored during its lifetime.”

Their work revealed that the type of chromophores present in Leonardo’s self portrait are “similar to those found in ancient and modern paper samples aged in extremely humid conditions or within a closed environment, which agrees with its documented history,” said Mauro Missori, a researcher at the Institute for Complex Systems, CNR, in Rome, Italy.

One of the most significant implications of their work is that the state of degradation of ancient paper can be measured and quantified by evaluation of the concentrations of chromophores in cellulose fibers. “The periodic repetition of our approach is fundamental to establishing the formation rate of chromophores within the self-portrait. Now our approach can serve as a precious tool to preserve and save not only this invaluable work of art, but others as well,” Conte noted.

Absolutely fascinating stuff to those of use who care about yellowing paper. (Having worked in an archives, I care deeply.) Here’s a link to and a citation for the study,

Visual degradation in Leonardo da Vinci’s iconic self-portrait: A nanoscale study by A. Mosca Conte, O. Pulci, M. C. Misiti, J. Lojewska, L. Teodonio1, C. Violante, and M. Missori. Appl. Phys. Lett. 104, 224101 (2014); http://dx.doi.org/10.1063/1.4879838

This is an open access study.

Chiral breathing at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS)

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An April 17, 2014 news item on ScienceDaily highlights some research about a polymer that has some special properties,

Electrically controlled glasses with continuously adjustable transparency, new polarisation filters, and even chemosensors capable of detecting single molecules of specific chemicals could be fabricated thanks to a new polymer unprecedentedly combining optical and electrical properties.

An international team of chemists from Italy, Germany, and Poland developed a polymer with unique optical and electric properties. Components of this polymer change their spatial configuration depending on the electric potential applied. In turn, the polarisation of transmitted light is affected. The material can be used, for instance, in polarisation filters and window glasses with continuously adjustable transparency. Due to its mechanical properties, the polymer is also perfectly suitable for fabrication of chemical sensors for selective detection and determination of optically active (chiral) forms of an analyte.

The research findings of the international team headed by Prof. Francesco Sannicolo from the Universita degli Studi di Milano were recently published in Angewandte Chemie International Edition.

“Until now, to give polymers chiral properties, chiral pendants were attached to the polymer backbone. In such designs the polymer was used as a scaffold only. Our polymer is exceptional, with chirality inherent to it, and with no pending groups. The polymer is both a scaffold and an optically active chiral structure. Moreover, the polymer conducts electricity,” comments Prof. Włodzimierz Kutner from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, one of the initiators of the research.

An April 17, 2014 IPC PAS news release (also on EurrekAlert), which originated the news item, describes chirality and the breathing metaphor with regard to this new polymer,

Chirality can be best explained by referring to mirror reflection. If two varieties of the same object look like their mutual mirror images, they differ in chirality. Human hands provide perhaps the most universal example of chirality, and the difference between the left and right hand becomes obvious if we try to place a left-handed glove on a right hand. The same difference as between the left and right hand is between two chiral molecules with identical chemical composition. Each of them shows different optical properties, and differently rotates plane-polarised light. In such a case, chemists refer to one chemical compound existing as two optical isomers called enantiomers.

The polymer presented by Prof. Sannicolo’s team was developed on the basis of thiophene, an organic compound composed of a five-member aromatic ring containing a sulphur atom. Thiophene polymerisation gives rise to a chemically stable polymer of high conductivity. The basic component of the new polymer – its monomer – is made of a dimer with two halves each made of two thiophene rings and one thianaphthene unit. The halves are connected at a single point and can partially be rotated with respect to each other by applying electric potential. Depending on the orientation of the halves, the new polymer either assumes or looses chirality. This behaviour is fully reversible and resembles a breathing system, whereas the “chiral breathing” is controlled by an external electric potential.

The development of a new polymer was initiated thanks to the research on molecular imprinting pursued at the Institute of Physical Chemistry of the PAS. The research resulted, for instance, in the development of polymers used as recognising units (receptors) in chemosensors, capable of selective capturing of molecules of various analytes, for instance nicotine, and also melamine, an ill-reputed chemical detrimental to human health, used as an additive to falsify protein content in milk and dairy products produced in China.

Generally, molecular imprinting consists in creating template-shaped cavities in polymer matrices with molecules of interest used first as cavity templates. Subsequently these templates are washed out from the polymer. As a result, the polymer contains traps with a shape and size matching those of molecules of the removed template. To be used as a receptor in chemosensor to recognize analyte molecules similar to templates or templates themselves, the polymer imprinted with these cavities must show a sufficient mechanical strength.

“Three-dimensional networks we attempted to build at the IPC PAS using existing two-dimensional thiophene derivatives just collapsed after the template molecules were removed. That’s why we asked for assistance our Italian partners, specialising in the synthesis of thiophene derivatives. The problem was to design and synthesise a three-dimensional thiophene derivative that would allow us for cross-linking of our polymers in three dimensions. The thiophene derivative synthesised in Milan has a stable three-dimensional structure, and the controllable chiral properties of the new polymer obtained after the derivative was polymerised, turned out a nice surprise for all of us”, explains Prof. Kutner.

Here’s a link to and a citation for the paper,

Potential-Driven Chirality Manifestations and Impressive Enantioselectivity by Inherently Chiral Electroactive Organic Films by Prof. Francesco Sannicolò1, Serena Arnaboldi, Prof. Tiziana Benincori, Dr. Valentina Bonometti, Dr. Roberto Cirilli, Prof. Lothar Dunsch, Prof. Włodzimierz Kutner, Prof. Giovanna Longhi, Prof. Patrizia R. Mussini, Dr. Monica Panigati, Prof. Marco Pierini, and Dr. Simona Rizzo. Angewandte Chemie International Edition Volume 53, Issue 10, pages 2623–2627, March 3, 2014. Article first published online: 5 FEB 2014 DOI: 10.1002/anie.201309585

© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This article is behind a paywall.

Transition metal dichalcogenides (molybdenum disulfide and tungsten diselenide) rock the graphene boat

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Anyone who’s read stories about scientific discovery knows that the early stages are characterized by a number of possibilities so the current race to unseat graphene as the wonder material of the nanoworld is a ‘business as usual’ sign although I imagine it can be confusing for investors and others hoping to make their fortunes. As for the contenders to the ‘wonder nanomaterial throne’, they are transition metal dichalcogenides: molybdenum disulfide and tungsten diselenide both of which have garnered some recent attention.

A March 12, 2014 news item on Nanwerk features research on molybdenum disulfide from Poland,

Will one-atom-thick layers of molybdenum disulfide, a compound that occurs naturally in rocks, prove to be better than graphene for electronic applications? There are many signs that might prove to be the case. But physicists from the Faculty of Physics at the University of Warsaw have shown that the nature of the phenomena occurring in layered materials are still ill-understood and require further research.

….

Researchers at the University of Warsaw, Faculty of Physics (FUW) have shown that the phenomena occurring in the crystal network of molybdenum disulfide sheets are of a slightly different nature than previously thought. A report describing the discovery, achieved in collaboration with Laboratoire National des Champs Magnétiques Intenses in Grenoble, has recently been published in Applied Physics Letters.

“It will not become possible to construct complex electronic systems consisting of individual atomic sheets until we have a sufficiently good understanding of the physics involved in the phenomena occurring within the crystal network of those materials. Our research shows, however, that research still has a long way to go in this field”, says Prof. Adam Babinski at the UW Faculty of Physics.

A March 12, 2014 Dept. of Physics University of Warsaw (FUW) news release, which originated the news item, describes the researchers’ ideas about graphene and alternative materials such as molybdenum disulfide,

“It will not become possible to construct complex electronic systems consisting of individual atomic sheets until we have a sufficiently good understanding of the physics involved in the phenomena occurring within the crystal network of those materials. Our research shows, however, that research still has a long way to go in this field”, says Prof. Adam Babiński at the UW Faculty of Physics.

The simplest method of creating graphene is called exfoliation: a piece of scotch tape is first stuck to a piece of graphite, then peeled off. Among the particles that remain stuck to the tape, one can find microscopic layers of graphene. This is because graphite consists of many graphene sheets adjacent to one another. The carbon atoms within each layer are very strongly bound to one another (by covalent bonds, to which graphene owes its legendary resilience), but the individual layers are held together by significantly weaker bonds (van de Walls [van der Waals] bonds). Ordinary scotch tape is strong enough to break the latter and to tear individual graphene sheets away from the graphite crystal.

A few years ago it was noticed that just as graphene can be obtained from graphite, sheets a single atom thick can similarly be obtained from many other crystals. This has been successfully done, for instance, with transition metals chalcogenides (sulfides, selenides, and tellurides). Layers of molybdenum disulfide (MoS2), in particular, have proven to be a very interesting material. This compound exists in nature as molybdenite, a crystal material found in rocks around the world, frequently taking the characteristic form of silver-colored hexagonal plates. For years molybdenite has been used in the manufacturing of lubricants and metal alloys. Like in the case of graphite, the properties of single-atom sheets of MoS2 long went unnoticed.

From the standpoint of applications in electronics, molybdenum disulfide sheets exhibit a significant advantage over graphene: they have an energy gap, an energy range within which no electron states can exist. By applying electric field, the material can be switched between a state that conducts electricity and one that behaves like an insulator. By current calculations, a switched-off molybdenum disulfide transistor would consume even as little as several hundred thousand times less energy than a silicon transistor. Graphene, on the other hand, has no energy gap and transistors made of graphene cannot be fully switched off.

The news release goes on to describe how the researchers refined their understanding of molybdenum disulfide and its properties,

Valuable information about a crystal’s structure and phenomena occurring within it can be obtained by analyzing how light gets scattered within the material. Photons of a given energy are usually absorbed by the atoms and molecules of the material, then reemitted at the same energy. In the spectrum of the scattered light one can then see a distinctive peak, corresponding to that energy. It turns out, however, that one out of many millions of photons is able to use some of its energy otherwise, for instance to alter the vibration or circulation of a molecule. The reverse situation also sometimes occurs: a photon may take away some of the energy of a molecule, and so its own energy slightly increases. In this situation, known as Raman scattering, two smaller peaks are observed to either side of the main peak.

The scientists at the UW Faculty of Physics analyzed the Raman spectra of molybdenum disulfide carrying on low-temperature microscopic measurements. The higher sensitivity of the equipment and detailed analysis methods enabled the team to propose a more precise model of the phenomena occurring in the crystal network of molybdenum disulfide.

“In the case of single-layer materials, the shape of the Raman lines has previously been explained in terms of phenomena involving certain characteristic vibrations of the crystal network. We have shown for molybdenum disulfide sheets that the effects ascribed to those vibrations must actually, at least in part, be due to other network vibrations not previously taken into account”, explains Katarzyna Gołasa, a doctorate student at the UW Faculty of Physics.

The presence of the new type of vibration in single-sheet materials has an impact on how electrons behave. As a consequence, these materials must have somewhat different electronic properties than previously anticipated.

Here’s what the rocks look like,

Molybdenum disulfide occurs in nature as molybdenite, crystalline material that frequently takes the characteristic form of silver-colored hexagonal plates. (Source: FUW)

I am not able to find the published research at this time (March 13, 2014).

The tungsten diselenide story is specifically application-centric. Dexter Johnson in a March 11, 2014 post on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website) describes the differing perspectives and potential applications suggested by the three teams that cooperated to produce papers united by a joint theme ,

The three research groups focused on optoelectronics applications of tungsten diselenide, but each with a slightly different emphasis.

The University of Washington scientists highlighted applications of the material for a light emitting diode (LED). The Vienna University of Technology group focused on the material’s photovoltaic applications. And, finally, the MIT [Massachusetts Institute of Technology] group looked at all of the optoelectronic applications for the material that would result from the way it can be switched from being a p-type to a n-type semiconductor.

Here are some details of the research from each of the institutions’ news releases.

A March 10, 2014 University of Washington (state) news release highlights their LED work,

University of Washington [UW] scientists have built the thinnest-known LED that can be used as a source of light energy in electronics. The LED is based off of two-dimensional, flexible semiconductors, making it possible to stack or use in much smaller and more diverse applications than current technology allows.

“We are able to make the thinnest-possible LEDs, only three atoms thick yet mechanically strong. Such thin and foldable LEDs are critical for future portable and integrated electronic devices,” said Xiaodong Xu, a UW assistant professor in materials science and engineering and in physics.

…

The UW’s LED is made from flat sheets of the molecular semiconductor known as tungsten diselenide, a member of a group of two-dimensional materials that have been recently identified as the thinnest-known semiconductors. Researchers use regular adhesive tape to extract a single sheet of this material from thick, layered pieces in a method inspired by the 2010 Nobel Prize in Physics awarded to the University of Manchester for isolating one-atom-thick flakes of carbon, called graphene, from a piece of graphite.

…

In addition to light-emitting applications, this technology could open doors for using light as interconnects to run nano-scale computer chips instead of standard devices that operate off the movement of electrons, or electricity. The latter process creates a lot of heat and wastes power, whereas sending light through a chip to achieve the same purpose would be highly efficient.

“A promising solution is to replace the electrical interconnect with optical ones, which will maintain the high bandwidth but consume less energy,” Xu said. “Our work makes it possible to make highly integrated and energy-efficient devices in areas such as lighting, optical communication and nano lasers.”

Here’s a link to and a citation for this team’s paper,

Electrically tunable excitonic light-emitting diodes based on monolayer WSe2 p–n junctions by Jason S. Ross, Philip Klement, Aaron M. Jones, Nirmal J. Ghimire, Jiaqiang Yan, D. G. Mandrus, Takashi Taniguchi, Kenji Watanabe, Kenji Kitamura, Wang Yao, David H. Cobden, & Xiaodong Xu. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.26 Published online 09 March 2014

This paper is behind a paywall.

A March 9, 2014 University of Vienna news release highlights their work on tungsten diselinide and its possible application in solar cells,

… With graphene as a light detector, optical signals can be transformed into electric pulses on extremely short timescales.

For one very similar application, however, graphene is not well suited for building solar cells. “The electronic states in graphene are not very practical for creating photovoltaics”, says Thomas Mueller. Therefore, he and his team started to look for other materials, which, similarly to graphene, can arranged in ultrathin layers, but have even better electronic properties.

The material of choice was tungsten diselenide: It consists of one layer of tungsten atoms, which are connected by selenium atoms above and below the tungsten plane. The material absorbs light, much like graphene, but in tungsten diselenide, this light can be used to create electrical power.

The layer is so thin that 95% of the light just passes through – but a tenth of the remaining five percent, which are absorbed by the material, are converted into electrical power. Therefore, the internal efficiency is quite high. A larger portion of the incident light can be used if several of the ultrathin layers are stacked on top of each other – but sometimes the high transparency can be a useful side effect. “We are envisioning solar cell layers on glass facades, which let part of the light into the building while at the same time creating electricity”, says Thomas Mueller.

Today, standard solar cells are mostly made of silicon, they are rather bulky and inflexible. Organic materials are also used for opto-electronic applications, but they age rather quickly. “A big advantage of two-dimensional structures of single atomic layers is their crystallinity. Crystal structures lend stability”, says Thomas Mueller.

Here’s a link to and a citation for the University of Vienna paper,

Solar-energy conversion and light emission in an atomic monolayer p–n diode by Andreas Pospischil, Marco M. Furchi, & Thomas Mueller. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.14 Published online 09 March 2014

This paper is behind a paywll.

Finally, a March 10, 2014 MIT news release details their work about material able to switch from p-type (p = positive) to a n-type (n = negative) semiconductors,

The material they used, called tungsten diselenide (WSe2), is part of a class of single-molecule-thick materials under investigation for possible use in new optoelectronic devices — ones that can manipulate the interactions of light and electricity. In these experiments, the MIT researchers were able to use the material to produce diodes, the basic building block of modern electronics.

Typically, diodes (which allow electrons to flow in only one direction) are made by “doping,” which is a process of injecting other atoms into the crystal structure of a host material. By using different materials for this irreversible process, it is possible to make either of the two basic kinds of semiconducting materials, p-type or n-type.

But with the new material, either p-type or n-type functions can be obtained just by bringing the vanishingly thin film into very close proximity with an adjacent metal electrode, and tuning the voltage in this electrode from positive to negative. That means the material can easily and instantly be switched from one type to the other, which is rarely the case with conventional semiconductors.

In their experiments, the MIT team produced a device with a sheet of WSe2 material that was electrically doped half n-type and half p-type, creating a working diode that has properties “very close to the ideal,” Jarillo-Herrero says.

By making diodes, it is possible to produce all three basic optoelectronic devices — photodetectors, photovoltaic cells, and LEDs; the MIT team has demonstrated all three, Jarillo-Herrero says. While these are proof-of-concept devices, and not designed for scaling up, the successful demonstration could point the way toward a wide range of potential uses, he says.

“It’s known how to make very large-area materials” of this type, Churchill says. While further work will be required, he says, “there’s no reason you wouldn’t be able to do it on an industrial scale.”

In principle, Jarillo-Herrero says, because this material can be engineered to produce different values of a key property called bandgap, it should be possible to make LEDs that produce any color — something that is difficult to do with conventional materials. And because the material is so thin, transparent, and lightweight, devices such as solar cells or displays could potentially be built into building or vehicle windows, or even incorporated into clothing, he says.

While selenium is not as abundant as silicon or other promising materials for electronics, the thinness of these sheets is a big advantage, Churchill points out: “It’s thousands or tens of thousands of times thinner” than conventional diode materials, “so you’d use thousands of times less material” to make devices of a given size.

Here’s a link to and a citation for the MIT paper,

Optoelectronic devices based on electrically tunable p–n diodes in a monolayer dichalcogenide by Britton W. H. Baugher, Hugh O. H. Churchill, Yafang Yang, & Pablo Jarillo-Herrero. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.25 Published online 09 March 2014

This paper is behind a paywall.

These are very exciting, if not to say, electrifying times. (Couldn’t resist the wordplay.)

Institute of Physical Chemistry of the Polish Academy of Sciences publishes e-book, ‘Horizons of Science’

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Informally titled, ‘Horizons of Science’, this e-book, intended for a general audience, is a 116 pp. document describing some of the latest science research being accomplished at the Institute of Physical Chemistry of the Polish Academy of Sciences. A March 5, 2014 Institute of Physical Chemistry of the Polish Academy of Sciences news release (also on EurekAlert) provides more detail about the book and its raison d’être,

Science knows everything and is always ready with a clear answer to any problem – this is what we think of science while leaving school and how the media present it. The real science is, however, different. What’s like? The answer can be found in an e-book prepared by the Institute of Physical Chemistry of the Polish Academy of Sciences [IPC PAS] in Warsaw.

Terawatts of power in laser pulses, low cost graphene coatings. Luminescent nanotubes and air-breathing biofuel cells. Proteins confronting nanoviscosity inside living cells, flows improving medical diagnostics and drug testing in bacterial colonies clustering in controlled microdroplets. These and dozens other topics are presented in an electronic book prepared by the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw. The research pursued at the IPC PAS is used to illustrate how science looks like where it is created and where the frontline of the contemporary chemistry meets physics, biology and technology. The e-book is available in Polish and English versions and can be downloaded free of charge from the Institute’s web page.

“One year ago we prepared a similar publication that was very warmly received. So we decided now to update and extend it, and first of all to make it available to a greater number of readers”, says Prof. Marcin Opałło, research director of the IPC PAS.

Polish chemistry has been for years at the world’s leading edge, and the IPC PAS is an institute ranked first in its group in the national ranking of the Polish Ministry of Science and Higher Education. The Institute is also Poland’s number one in the ranking of the SCImago Institutions Rankings (SIR) in the prestigious Q1 classification based on the number of publications in 25% world’s highest ranked scientific journals. Thus, the articles in the book report competently on topics from the very frontline of the contemporary, state-of-the-art chemistry.

The publication includes a few dozen of popular science articles reporting the research of the scientists from the Institute of Physical Chemistry of the PAS. The articles are grouped into three chapters related to making discoveries, getting deeper understanding of nature, and applying the research findings in practice. So presented, science appears as a fascinating field, full of riddles, unceasingly aiming at extending of human perception and human capabilities.

“True science is the love for continuous exploration. That’s why the book does not present ready answers but rather real research problems, often not fully solved, faced by contemporary researchers. We wanted to present the readers a reliable, well-founded knowledge, but also to show the quest for ways leading to the knowledge, the sources of inspiration, as well as the incessant wish to verify the information gained earlier that is so characteristic for the world of science”, says Jarek Chrostowski, journalist and scientific editor responsible for the text of the publication.

Reading the e-book from the Institute of Physical Chemistry of the PAS the reader travels to remote interstellar clouds, where the density of matter is lower than the laboratory vacuum and where surprisingly complicated molecules can be still discovered. He or she learns how astronomy can be used in testing samples for materials engineering, what problems faces science while attempting to study the rate of chemical reactions in bacterial and mammalian cells, and is no more surprised why cloned cat is different from the original. The reader discovers surprising properties of the phenomena as common as evaporation – and so unusual as proton tunnelling in molecules, and learns how to create molecular cages delivering drugs to selected points of the human body, how to detect single molecules of harmful agents and why we should study the performance of molecular motors.

The last, fourth chapter of the e-book presents organisational efforts of the Institute of Physical Chemistry of the PAS aiming at the development of science and Polish scientific community.

“With our publication we want to send a clear message especially to young people. Yes, chemistry and physics are interesting, moreover, they are fascinating, and additionally there is a plenty to do in these fields of science. Every open mind can join us and, as ourselves, build up knowledge – for his or her own curiosity and for the good of the entire society”, notices Prof. Robert Holyst, the director of the IPC PAS.

You can download the book from IPC PAS homepage (hopefully this links to the English language version of the page; if not, click on the Union Jack (British) flag below the page’s navigation bar or you can access the English language version of the book directly from this link. While it’s not primarily focused on nanoscience, much of the content could be described with that term.

Carbon dioxide as a source for new nanomaterials

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Polish researchers have made a startling suggestion (from a Jan. 23, 2014 news item on Nanowerk),

In common perception, carbon dioxide is just a greenhouse gas, one of the major environmental problems of mankind. For Warsaw chemists CO2 became, however, something else: a key element of reactions allowing for creation of nanomaterials with unprecedented properties.

In reaction with carbon dioxide, appropriately designed chemicals allowed researchers from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw and the Faculty of Chemistry, Warsaw University of Technology, (WUT) for production of unprecedented nanomaterials.

Here’s an image the researchers use to illustrate their work,

Yellow tennis balls, spatially integrated in an adamant-like structure, symbolise crystal lattice of the microporous material resulting from self-assembly of nanoclusters. Orange balls imitate gas molecules that can adsorb in this material. The presentation is performed by Katarzyna Sołtys, a doctoral student from the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. (Source: IPC PAS, Grzegorz Krzyżewski).

The Jan. 23, 2014 IPC news release, which originated the news item, describes the work in more detail,

Carbon dioxide (CO2) is a natural component of Earth’s atmosphere. It is the most abundant carbon-based building block, and is involved in the synthesis of glucose, an energy carrier and building unit of paramount importance for living organisms.

“Carbon dioxide has been for years used in industrial synthesis of polymers. On the other hand, there has been very few research papers reporting fabrication of inorganic functional materials using CO2”, says Kamil Sokołowski, a doctoral student in IPC PAS.

Prof. Lewiński’s [Janusz Lewiński (IPC PAS, WUT)] group has shown that appropriately designed precursor compounds in reaction with carbon dioxide lead to fabrication of a microporous material (with pore diameters below 2 nm) resulting from self-assembly of luminescent nanoclusters. Novel microporous material, composed of building blocks with zinc carbonate core encapsulated in appropriately designed organic shell (hydroxyquinoline ligands), is highly luminescent, with photoluminescence quantum yield significantly higher than those of classical fluorescent compounds used in state-of-the-art OLEDs.

“Using carbon dioxide as a building block we were able to construct a highly porous and really highly luminescent material. Can it be used for construction of luminescent diodes or sensing devices? The discovery is new, the research work on the novel material is in progress, but we are deeply convinced that the answer is: yes”, says Sokołowski.

Already now it can be said that the novel material enjoys considerable interest. Polish and international patent applications were filed for the invention and the implementation work in cooperation with a joint venture company is in progress.

The design of precursors was inspired by nature, in particular by the binding of carbon dioxide in enzymatic systems of carbonic anhydrase, an enzyme responsible for fast metabolism of CO2 in human body. Effective enzyme activity is based on its active centre, where a hydroxyzinc (ZnOH) type reaction system is located.

“A hydroxyzinc reaction system occurs also in molecules of alkylzinc compounds, designed by us and used for fixation of carbon dioxide”, explains Sokołowski and continues: “These compounds are of particular interest for us, because in addition to hydroxyl group they contain also a reactive metal-carbon bond. It means that both the first and the second reaction system can participate in consecutive chemical transformations of such precursors”.

The research related to the chemistry of alkylhydroxyzinc compounds has an over 150 years of history and its roots are directly connected to the birth of organometallic chemistry. It was, however, only in 2011 and 2012 when Prof. Lewiński’s group has presented the first examples of stable alkylhydroxyzinc compounds obtained as a result of rationally designed synthesis.

The strategy for materials synthesis using carbon dioxide and appropriate alkylhydroxyzinc precursors, discovered by the researchers from Warsaw, seems to be a versatile tool for production of various functional materials. Depending on the composition of the reagents and the process conditions, a mesoporous material (with pore diameter from 2 to 50 nm) composed of zinc carbonate nanoparticles or multinuclear zinc nanocapsules for prospective applications in supramolecular chemistry can be obtained in addition to the material described above.

Further research of Prof. Lewiński’s group has shown that the mesoporous materials based on ZnCO3-nanoparticles can be transformed into zinc oxide (ZnO) aerogels. Mesoporous materials made of ZnO nanoparticles with extended surface can be used as catalytic fillings, allowing for and accelerating reactions of various gaseous reagents. Other potential applications are related to semiconducting properties of zinc oxide. That’s why the novel materials can be used in future in photovoltaic cells or as a major component of semiconductor sensing devices.

Good luck to the researchers as they find ways to turn a greenhouse gas into something useful.

FrogHeart

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