Tag Archives: Korea

Inspiration from the sea for titanium implants (mussels) and adhesive panels for flexible sensors (octopuses/octopi/octopodes)

I have two sea-inspired news bits both of which concern adhesion.

Mussels and titanium implants

A July 8, 2016 news item on ScienceDaily features some mussel-inspired research from Japan into how to make better titanium implants,

Titanium is used medically in applications such as artificial joints and dental implants. While it is strong and is not harmful to tissues, the metal lacks some of the beneficial biological properties of natural tissues such as bones and natural teeth. Now, based on insights from mussels–which are able to attach themselves very tightly to even metallic surfaces due to special proteins found in their byssal threads–scientists from RIKEN have successfully attached a biologically active molecule to a titanium surface, paving the way for implants that can be more biologically beneficial.

A July 11, 2016 RIKEN press release (also on EurekAlert but dated July 8, 2016), which originated the news item, provides more information,

The work began from earlier discoveries that mussels can attach to smooth surfaces so effectively thanks to a protein, L-DOPA, which is known to be able to bind very strongly to smooth surfaces such as rocks, ceramics, or metals (…). Interestingly, the same protein functions in humans as a precursor to dopamine, and is used as a treatment for Parkinson’s disease.

According to Chen Zhang of the RIKEN Nano Medical Engineering Laboratory, the first author of the paper published in Angewandte Chemie, “We thought it would be interesting to try to use various techniques to attach a biologically active protein—in our case we chose insulin-like growth factor-1, a promoter of cell proliferation—to a titanium surface like those used in implants” (…).

Using a combination of recombinant DNA technology and treatment with tyrosinase, they were able to create a hybrid protein that contained active parts of both the growth factor and L-DOPA. Tests showed that the proteins were able to fold normally, and further experiments in cell cultures demonstrated that the IGF-1 was still functioning normally. Thanks to the incorporation of the L-DOPA, the team was able to confirm that the proteins bound strongly to the titanium surface, and remained attached even when the metal was washed with phosphate-buffered saline, a water-based solution. Zhang says, “This is similar to the powerful properties of mussel adhesive, which can remain fixed to metallic materials even underwater.”

According to Yoshihiro Ito, Team Leader of the Emergent Bioengineering Research Team of the RIKEN Center for Emergent Matter Science, “We are very excited by this finding, because the modification process is a universal one that could be used with other proteins. It could allow us to prepare new cell-growth enhancing materials, with potential applications in cell culture systems and regenerative medicine. And it is particularly interesting that this is an example of biomimetics, where nature can teach us new ways to do things. The mussel has given us insights that could be used to allow us to live healthier lives.”

The work was done by RIKEN researchers in collaboration with Professor Peibiao Zhang of the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, and Professor Yi Wang of the School of Pharmaceutical Sciences, Jilin University. The work was partially supported by the Japan Society for the Promotion of Science KAKENHI (Grant Number 15H01810 and 22220009), CAS-JSPS joint fund (GJHZ1519), and RIKEN MOST joint project.

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

A Bioorthogonal Approach for the Preparation of a Titanium-Binding Insulin-like Growth-Factor-1 Derivative by using Tyrosinase by Chen Zhang, Hideyuki Miyatake, Yu Wang, Takehiko Inaba, Yi Wang, Peibiao Zhang, and Prof. Yoshihiro Ito. Angewandte Chemie International Edition DOI: 10.1002/anie.201603155 Version of Record online: 6 JUL 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Octopuses/octopi/octopodes and adhesive panels

Before launching into the science part of this news bit, here’s some grammar (from the Octopus Wikipedia entry; Note: Links have been removed),

The standard pluralized form of “octopus” in the English language is “octopuses” /ˈɒktəpʊsɪz/,[10] although the Ancient Greek plural “octopodes” /ɒkˈtɒpədiːz/, has also been used historically.[9] The alternative plural “octopi” — which misguidedly assumes it is a Latin “-us”-word — is considered grammatically incorrect.[11][12][13][14] It is nevertheless used enough to make it notable, and was formally acknowledged by the descriptivist Merriam-Webster 11th Collegiate Dictionary and Webster’s New World College Dictionary. The Oxford English Dictionary (2008 Draft Revision)[15] lists “octopuses”, “octopi”, and “octopodes”, in that order, labelling “octopodes” as rare and noting that “octopi” derives from the apprehension that octōpus comes from Latin.[16] In contrast, New Oxford American Dictionary (3rd Edition 2010) lists “octopuses” as the only acceptable pluralization, with a usage note indicating “octopodes” as being still occasionally used but “octopi” as being incorrect.[17]

Now the news. A July 12, 2016 news item on Nanowerk highlights some research into adhesives and octopuses,

With increased study of bio-adhesives, a significant effort has been made in search for novel adhesives that will combine reversibility, repeated usage, stronger bonds and faster bonding time, non-toxic, and more importantly be effective in wet and other extreme conditions.

A team of Korean scientists-made up of scientists from Korea Institute of Science and Technology (KIST) and UNIST has recently found a way to make building flexible pressure sensors easier–by mimicking the suction cups on octopus’s tentacles.

A July 5, 2016 UNIST (Ulsan National Institute of Science and Technology) press release, which originated the news item, provides more information,

According to the research team, “Although flexible pressure sensors might give future prosthetics and robots a better sense of touch, building them requires a lot of laborious transferring of nano- and microribbons of inorganic semiconductor materials onto polymer sheets.”

In search of an easier way to process this transfer printing, Prof. Hyunhyub Ko (School of Energy and Chemical Engineering, UNIST) and his colleagues turned to the octopus suction cups for inspiration.

An octopus uses its tentacles to move to a new location and uses suction cups underneath each tentacle to grab onto something. Each suction cup contains a cavity whose pressure is controlled by surrounding muscles. These can be made thinner or thicker on demand, increasing or decreasing air pressure inside the cup, allowing for sucking and releasing as desired.

By mimicking muscle actuation to control cavity-pressure-induced adhesion of octopus suckers, Prof. Ko and his team engineered octopus-inspired smart adhesive pads. They used the rubbery material polydimethylsiloxane (PDMS) to create an array of microscale suckers, which included pores that are coated with a thermally responsive polymer to create sucker-like walls.

The team discovered that the best way to replicate organic nature of muscle contractions would be through applied heat. Indeed, at room temperature, the walls of each pit sit in an ‘open’ state, but when the mat is heated to 32°C, the walls contract, creating suction, therby allowing the entire mate to adhere to a material (mimicking the suction function of an octopus). The adhesive strength also spiked from .32 kilopascals to 94 kilopascals at high temperature.

The team reports that the mat worked as envisioned—they made some indium gallium arsenide transistors that sat on a flexible substrate and also used it to move some nanomaterials to a different type of flexible material.

Prof. Ko and his team expect that their smart adhesive pads can be used as the substrate for wearable health sensors, such as Band-Aids or sensors that stick to the skin at normal body temperatures but fall off when rinsed under cold water.

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

Octopus-Inspired Smart Adhesive Pads for Transfer Printing of Semiconducting Nanomembranes by Hochan Lee, Doo-Seung Um, Youngsu Lee, Seongdong Lim, Hyung-jun Kim,  and Hyunhyub Ko. Advanced Materials DOI: 10.1002/adma.201601407 Version of Record online: 20 JUN 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Korea Advanced Institute of Science and Technology (KAIST) at summer 2016 World Economic Forum in China

From the Ideas Lab at the 2016 World Economic Forum at Davos to offering expertise at the 2016 World Economic Forum in Tanjin, China that is taking place from June 26 – 28, 2016.

Here’s more from a June 24, 2016 KAIST news release on EurekAlert,

Scientific and technological breakthroughs are more important than ever as a key agent to drive social, economic, and political changes and advancements in today’s world. The World Economic Forum (WEF), an international organization that provides one of the broadest engagement platforms to address issues of major concern to the global community, will discuss the effects of these breakthroughs at its 10th Annual Meeting of the New Champions, a.k.a., the Summer Davos Forum, in Tianjin, China, June 26-28, 2016.

Three professors from the Korea Advanced Institute of Science and Technology (KAIST) will join the Annual Meeting and offer their expertise in the fields of biotechnology, artificial intelligence, and robotics to explore the conference theme, “The Fourth Industrial Revolution and Its Transformational Impact.” The Fourth Industrial Revolution, a term coined by WEF founder, Klaus Schwab, is characterized by a range of new technologies that fuse the physical, digital, and biological worlds, such as the Internet of Things, cloud computing, and automation.

Distinguished Professor Sang Yup Lee of the Chemical and Biomolecular Engineering Department will speak at the Experts Reception to be held on June 25, 2016 on the topic of “The Summer Davos Forum and Science and Technology in Asia.” On June 27, 2016, he will participate in two separate discussion sessions.

In the first session entitled “What If Drugs Are Printed from the Internet?” Professor Lee will discuss the future of medicine being impacted by advancements in biotechnology and 3D printing technology with Nita A. Farahany, a Duke University professor, under the moderation of Clare Matterson, the Director of Strategy at Wellcome Trust in the United Kingdom. The discussants will note recent developments made in the way patients receive their medicine, for example, downloading drugs directly from the internet and the production of yeast strains to make opioids for pain treatment through systems metabolic engineering, and predicting how these emerging technologies will transform the landscape of the pharmaceutical industry in the years to come.

In the second session, “Lessons for Life,” Professor Lee will talk about how to nurture life-long learning and creativity to support personal and professional growth necessary in an era of the new industrial revolution.

During the Annual Meeting, Professors Jong-Hwan Kim of the Electrical Engineering School and David Hyunchul Shim of the Aerospace Department will host, together with researchers from Carnegie Mellon University and AnthroTronix, an engineering research and development company, a technological exhibition on robotics. Professor Kim, the founder of the internally renowned Robot World Cup, will showcase his humanoid micro-robots that play soccer, displaying their various cutting-edge technologies such as imaging processing, artificial intelligence, walking, and balancing. Professor Shim will present a human-like robotic piloting system, PIBOT, which autonomously operates a simulated flight program, grabbing control sticks and guiding an airplane from take offs to landings.

In addition, the two professors will join Professor Lee, who is also a moderator, to host a KAIST-led session on June 26, 2016, entitled “Science in Depth: From Deep Learning to Autonomous Machines.” Professors Kim and Shim will explore new opportunities and challenges in their fields from machine learning to autonomous robotics including unmanned vehicles and drones.

Since 2011, KAIST has been participating in the World Economic Forum’s two flagship conferences, the January and June Davos Forums, to introduce outstanding talents, share their latest research achievements, and interact with global leaders.

KAIST President Steve Kang said, “It is important for KAIST to be involved in global talks that identify issues critical to humanity and seek answers to solve them, where our skills and knowledge in science and technology could play a meaningful role. The Annual Meeting in China will become another venue to accomplish this.”

I mentioned KAIST and the Ideas Lab at the 2016 Davos meeting in this Nov. 20, 2015 posting and was able to clear up my (and possible other people’s) confusion as to what the Fourth Industrial revolution might be in my Dec. 3, 2015 posting.

The Canadian nano scene as seen by the OECD (Organization for Economic Cooperation and Development)

I’ve grumbled more than once or twice about the seemingly secret society that is Canada’s nanotechnology effort (especially health, safety, and environment issues) and the fact that I get most my information from Organization for Economic Cooperation and Development (OECD) documents. That said, thank you to Lynne Bergeson’s April 8, 2016 post on Nanotechnology Now for directions to the latest OECD nano document,

The Organization for Economic Cooperation and Development recently posted a March 29, 2016, report entitled Developments in Delegations on the Safety of Manufactured Nanomaterials — Tour de Table. … The report compiles information, provided by Working Party on Manufactured Nanomaterials (WPMN) participating delegations, before and after the November 2015 WPMN meeting, on current developments on the safety of manufactured nanomaterials.

It’s an international roundup that includes: Australia, Austria, Belgium, Canada, Germany, Japan, Korea, the Netherlands, Switzerland, Turkey, United Kingdom, U.S., and the European Commission (EC), as well as the Business and Industry Advisory Committee to the OECD (BIAC) and International Council on Animal Protection in OECD Programs (ICAPO).

As usual, I’m focusing on Canada. From the DEVELOPMENTS IN DELEGATIONS ON THE SAFETY OF MANUFACTURED NANOMATERIALS – TOUR DE TABLE Series on the Safety of Manufactured Nanomaterials No. 67,

CANADA
National  developments  on  human  health  and  environmental  safety  including  recommendations, definitions, or discussions related to adapting or applying existing regulatory systems or the drafting of new laws/ regulations/amendments/guidance materials A consultation document on a Proposed Approach to Address Nanoscale Forms of Substances on the Domestic  Substances  List was  published  with  a  public  comment  period  ending on  May  17,  2015. The proposed approach outlines the Government’s plan to address nanomaterials considered in commerce in Canada (on  Canada’s  public inventory).  The  proposal is a stepwise  approach to  acquire  and  evaluate information,  followed  by  any  necessary  action. A  follow-up  stakeholder  workshop  is  being  planned  to discuss  next  steps  and  possible  approaches  to prioritize  future  activities. The  consultation document  is available at: http://www.ec.gc.ca/lcpe-cepa/default.asp?lang=En&n=1D804F45-1

A mandatory information gathering survey was published on July 25, 2015. The purpose of the survey is to collect information to determine the commercialstatus of certain nanomaterials in Canada. The survey targets  206  substances  considered  to  be  potentially  in commerce  at  the  nanoscale. The  list  of  206 substances was developed using outcomes from the Canada-United States Regulatory Cooperation Council (RCC)  Nanotechnology  Initiative  to  identify nanomaterial  types. These  nanomaterial  types  were  cross-referenced  with  the Domestic  Substances  List to  develop  a  preliminary  list  of  substances  which are potentially intentionally manufactured at the nanoscale. The focus of the survey aligns with the Proposed Approach to  Address  Nanoscale  Forms  of  Substances  on  the Domestic  Substances  List (see  above)  and certain  types  of  nanomaterials  were  excluded  during the  development  of  the  list  of  substances. The information  being  requested  by  the  survey  includes substance  identification,  volumes,  and  uses.  This information will feed into the Government’s proposed approach to address nanomaterials on the Domestic Substances List. Available at: http://gazette.gc.ca/rp-pr/p1/2015/2015-07-25/html/notice-avis-eng.php

Information on:

a.risk  assessment  decisions, including  the  type  of:  (a)  nanomaterials  assessed; (b) testing recommended; and (c) outcomes of the assessment;

Four substances were notified to the program since the WPMN14 – three surface modified substances and  one  inorganic  substance.  No  actions,  including  additional  data requests,  were  taken  due  to  low expected  exposures  in  accordance  with  the New  Substances  Notifications  Regulations  (Chemicals and Polymers) (NSNR) for two of the substances.  Two of the substances notified were subject to a Significant New Activity Notice. A Significant New Activity notice is an information gathering tool used to require submission  of  additional  information  if  it  is suspected  that  a  significant  new  activity  may  result in  the substance becoming toxic under the Canadian Environmental Protection Act, 1999.

b.Proposals, or modifications to previous regulatory decisions

As  part  of  the  Government’s  Chemicals  Management Plan,  a  review  is  being  undertaken  for  all substances  which  have  been  controlled through  Significant  New  Activity  (SNAc)  notices (see  above).  As part  of  this  activity,  the  Government  is  reviewing past  nanomaterials  SNAc  notices  to  see  if  new information  is  available  to  refine  the  scope  and information  requirements.    As  a  result  of  this  review, 9 SNAc  notices  previously  in  place  for  nanomaterials have  been  rescinded.    This  work  is  ongoing,  and  a complete review of all nanomaterial SNAcs is currently planned to be completed in 2016.

Information related to good practice documents

The Canada-led,  ISO  standards project, ISO/DTR  19716 Nanotechnologies — Characterization  of cellulose  nanocrystals, [emphasis mine] initiated  in  April 2014, is  now at Committee  Draft  (CD)  3-month  ISO ballot, closing    Aug 31, 2015. Ballot comments will be addressed during JWG2 Measurement and Characterization working  group meetings  at  the 18th Plenary  of  ISO/TC229, Nanotechnologies,  being held in Edmonton, Alberta, Sep. 28 – Oct. 2, 2015.

Research   programmes   or   strategies   designed   to  address   human   health   and/   or environmental safety aspects of nanomaterials

Scientific research

Environment Canada continues to support various academic and departmental research projects. This research has to date included studying fate and effects of nanomaterials in the aquatic, sediment, soil, and air  compartments. Funding  in  fiscal  2015-16  continues  to  support  such  projects,  including  sub-surface transportation, determining key physical-chemical parameters to predict ecotoxicity, and impacts of nano-silver [silver nanoparticles]  addition  to  a  whole  lake  ecosystem [Experimental Lakes Area?]. Environment  Canada  has  also  partnered  with  the National Research  Council  of  Canada  recently  to  initiate  a project  on  the  development  of  test  methods  to identify surfaces of nanomaterials for the purposes of regulatory identification and to support risk assessments. In addition,  Environment  Canada  is  working  with  academic laboratories in  Canada  and  Germany  to  prepare guidance to support testing of nanoparticles using the OECD Test Guideline for soil column leaching.

Health  Canada  continues  its  research  efforts  to  investigate  the  effects  of  surface-modified  silica nanoparticles. The   aims   of   these   projects   are  to:   (1) study the importance of size and surface functionalization;  and  (2)  provide a genotoxic profile and  to  identify  mechanistic  relationships  of  particle properties  to  elicited  toxic  responses.  A manuscript reporting  the in  vitro genotoxic,  cytotoxic and transcriptomic  responses  following  exposure  to  silica  nanoparticles  has  recently  been  submitted to  a  peer reviewed journal and is currently undergoing review. Additional manuscripts reporting the toxicity results obtained to date are in preparation.

Information on public/stakeholder consultations;

A consultation document on a Proposed Approach to Address Nanoscale Forms of Substances on the Domestic  Substances  List was  published  with a  public  comment  period ending  on May  17,  2015  (see Question  1).  Comments  were  received  from approximately  20  stakeholders  representing  industry and industry  associations,  as  well  as  non-governmental  organizations. These  comments  will  inform  decision making to address nanomaterials in commerce in Canada.

Information on research or strategies on life cycle aspects of nanomaterials

Canada, along with Government agencies in the United States, Non-Governmental Organizations and Industry,  is  engaged  in  a  project  to  look  at releases  of  nanomaterials  from  industrial  consumer  matrices (e.g., coatings). The objectives of the NanoRelease Consumer Products project are to develop protocols or
methods (validated  through  interlaboratory  testing) to  measure  releases  of  nanomaterials  from  solid matrices as a result of expected uses along the material life cycle for consumer products that contain the nanomaterials. The  project  is  currently  in  the  advanced  stages  of Phase  3  (Interlaboratory  Studies).  The objectives of Phase 3 of the project are to develop robust methods for producing and collecting samples of CNT-epoxy  and  CNT-rubber  materials  under  abrasion  and  weathering scenarios,  and  to  detect  and quantify, to the extent possible, CNT release fractions. Selected laboratories in the US, Canada, Korea and the European Community are finalising the generation and analysis of sanding and weathering samples and the    results    are    being    collected    in    a   data    hub    for    further    interpretation    and    analysis.

Additional details about the project can be found at the project website: http://www.ilsi.org/ResearchFoundation/RSIA/Pages/NanoRelease1.aspx

Under the OECD Working Party on Resource Productivity and Waste (WPRPW), the expert group on waste containing nanomaterials has developed four reflection papers on the fate of nanomaterials in waste treatment  operations.  Canada  prepared the  paper  on  the  fate  of  nanomaterials in  landfills;  Switzerland on the  recycling  of  waste  containing  nanomaterials;  Germany  on  the  incineration  of  waste  containing nanomaterials;  and  France  on  nanomaterials  in wastewater  treatment.  The  purpose  of  these  papers is to provide  an  overview  of  the  existing  knowledge  on the  behaviour  of  nanomaterials  during  disposal operations and identify the information gaps. At the fourth meeting of the WPRPW that took place on 12-14 November 2013, three of the four reflection papers were considered by members. Canada’s paper was presented and discussed at the fifth meeting of the WPRPRW that took place on 8-10 December 2014. The four  papers  were  declassified  by  EPOC  in  June  2015, and  an  introductory  chapter  was  prepared  to  draw these  papers  together. The introductory  chapter  and accompanying  papers  will  be  published in  Fall  2015. At  the sixth  meeting  of  the  WPRPW  in  June – July  2015,  the  Secretariat  presented  a  proposal  for an information-sharing  platform  that  would  allow  delegates  to  share research  and  documents  related  to nanomaterials. During a trial phase, delegates will be asked to use the platform and provide feedback on its use at the next meeting of the WPRPW in December 2015. This information-sharing platform will also be accessible to delegates of the WPMN.

Information related to exposure measurement and exposure mitigation.

Canada and the Netherlands are co-leading a project on metal impurities in carbon nanotubes. A final version  of  the  report  is  expected  to  be ready for WPMN16. All  research has  been completed (e.g. all components are published or in press and there was a presentation by Pat Rasmussen to SG-08 at the Face-to-Face Meeting in Seoul June 2015). The first draft will be submitted to the SG-08 secretariat in autumn 2015. Revisions  will  be  based  on  early  feedback  from  SG-08  participants.  The  next  steps  depend  on  this feedback and amount of revision required.

Information on past, current or future activities on nanotechnologies that are being done in co-operation with non-OECD countries.

A webinar between ECHA [European Chemicals Agency], the US EPA [Environmental Protection Agency] and Canada was hosted by Canada on April 16, 2015. These are  regularly  scheduled  trilateral  discussions  to keep  each  other  informed  of  activities  in  respective jurisdictions.

In  March 2015, Health  Canada  hosted  3  nanotechnology knowledge  transfer sessions  targeting Canadian  government  research  and  regulatory  communities  working  in  nanotechnology.  These  sessions were  an  opportunity  to  share  information  and perspectives  on  the  current  state  of  science supporting  the regulatory  oversight  of  nanomaterials with  Government.  Presenters  provided  detailed  outputs  from  the OECD WPMN including: updates on OECD test methods and guidance documents; overviews of physical-chemical properties, as well as their relevance to toxicological testing and risk assessment; ecotoxicity and fate   test   methods;   human   health   risk   assessment   and   alternative   testing   strategies;   and exposure measurement  and  mitigation.  Guest  speakers  included  Dr  Richard  C.  Pleus  Managing  Director  and  Director of Intertox, Inc and Dr. Vladimir Murashov Special Assistant on Nanotechnology to the Director of National Institute for Occupational Safety and Health (NIOSH).

On   March   4-5, 2015, Industry   Canada   and   NanoCanada co-sponsored  “Commercializing Nanotechnology  in  Canada”,  a  national  workshop  that brought  together  representatives  from  industry, academia and government to better align Canada’s efforts in nanotechnology.  This workshop was the first of  its  kind  in  Canada. It  also  marked  the  official  launch  of  NanoCanada (http://nanocanada.com/),  a national  initiative  that  is  bringing  together stakeholders  from  across  Canada  to  bridge  the  innovation  gap and stimulates emerging technology solutions.

It’s nice to get an update about what’s going on. Despite the fact this report was published in 2016 the future tense is used in many of the verbs depicting actions long since accomplished. Maybe this was a cut-and-paste job?

Moving on, I note the mention of the Canada-led,  ISO  standards project, ISO/DTR  19716 Nanotechnologies — Characterization  of cellulose  nanocrystals (CNC). For those not familiar with CNC, the Canadian government has invested hugely in this material derived mainly from trees, in Canada. Other countries and jurisdictions have researched nanocellulose derived from carrots, bananas, pineapples, etc.

Finally, it was interesting to find out about the existence of  NanoCanada. In looking up the Contact Us page, I noticed Marie D’Iorio’s name. D’Iorio, as far as I’m aware, is still the Executive Director for Canada’s National Institute of Nanotechnology (NINT) or here (one of the National Research Council of Canada’s institutes). I have tried many times to interview someone from the NINT (Nils Petersen, the first NINT ED and Martha Piper, a member of the advisory board) and more recently D’Iorio herself only to be be met with a resounding silence. However, there’s a new government in place, so I will try again to find out more about the NINT, and, this time, NanoCanada.

Turning sunlight into hydrogen (a Korean project)

A Feb. 17, 2016 news item on Nanowerk describes a new technique for solar water-splitting (turning sunlight into hydrogen),

A team of Korean researchers, affiliated with UNIST [Ulsan National Institute of Science and Technology] has recently pioneered in developing a new type of multilayered (Au NPs/TiO2/Au) photoelectrode that boosts the ability of solar water-splitting to produce hydrogen. According to the research team, this special photoelectrode, inspired by the way plants convert sunlight into energy is capable of absorbing visible light from the sun, and then using it to split water molecules (H2O) into hydrogen and oxygen.

A Feb. 1, 2016 UNIST news release, which originated the news item, expands on the theme,

This multilayered photoelectrode takes the form of two-dimensional hybrid metal-dielectric structure, which mainly consists of three layers of gold (Au) film, ultrathin TiO2 layer (20 nm), and gold nanoparticles (Au NPs). In a study, reported in the January 21, 2016 issue of Nano Energy, the team reported that this promising photoelectrode shows high light absorption of about 90% in the visible range 380–700 nm, as well as significant enhancement in photo-catalytic applications.

The researchers have made an image illustrating their work available,

Two-dimensional metastructured film with Titanium Oxide is fabricated as a photo-catalytic photoanode with exceptional visible light absorption. Courtesy: UNIST

Two-dimensional metastructured film with Titanium Oxide is fabricated as a photo-catalytic photoanode with exceptional visible light absorption. Courtesy: UNIST

Back to the news release,

Many structural designs, such as hierarchical and branched assemblies of nanoscale materials have been suggested to increase the UV-visible absorption and to enhance water-splitting efficiency. However, through incorporation of plasmonic metal nanoparticles (i.e. Au) to TiO2 structures, their photoelectrodes have shown to enhance the photoactivity in the entire UV-visible region of solar spectrum when compared with the existing ones, the team reports.

Prof. Jeong Min Baik of UNIST (School of Materials Science and Engineering) states, “Several attemps have been made to use UV-based photoelectrodes for hydrogen production, but this is the first time to use the metal-dielectric hybrid-structured film with TiO2 for oxygen production.” Moreover, according to Prof. Baik, this special type of photoelectrode uses approximately 95% of the visible spectrum of sunlight, which makes up a substantial portion (40%) of full sunlight. He adds, “The developed technology is expected to improve hydrogen production efficiency.”

Prof. Heon Lee (Korean University) states, “This metal-dielectric hybrid-structured film is expected to further reduce the overall cost of producing hydrogen, as it doesn’t require complex operation processes.” He continues by saying, “Using nanoimprint lithography, mass production of hydrogen will be soon possible.”

Prof. Baik adds, “This simple system may serve as an efficient platform for solar energy conversion, utilizing the whole UV-visible range of solar spectrum based on two-dimensional plasmonic photoelectrodes.”

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

Two-dimensional metal-dielectric hybrid-structured film with titanium oxide for enhanced visible light absorption and photo-catalytic application by Joonmo Park, Hee Jun Kim, SangHyeon Nam, Hyowook Kim, Hak-Jong Choi, Youn Jeong Jang, Jae Sung Lee, Jonghwa Shin, Heon Lee, Jeong Min Baik. Nano Energy Volume 21, March 2016, Pages 115–122 doi:10.1016/j.nanoen.2016.01.004

This paper is behind a paywall.

Korean researchers fabricate cross-shaped memristors

I’ve been a bit late getting this Korean research concerning memristors into a posting. A Jan. 30, 2016 news item on Nanotechnology Now announces a new means of fabricating memristors,

Along with the fast development of modern information technology, charge-based memories, such as DRAM and flash memory, are being aggressively scaled down to meet the current trend of small size devices. A memory device with high density, faster speed, and low power consumption is desired to satisfy Moore’s law in the next few decades. Among the candidates of next-generation memory devices, cross-bar-shaped non-volatile resistive memory (memristor) is one of the most attractive solutions for its non-volatility, faster access speed, ultra-high density and easier fabrication process.

Conventional memristors are usually fabricated through conventional optical, imprint, and e-beam lithographic approaches. However, to meet Moore’s law, the assembly of memristors comprised of 1-dimensional (1D) nanowires must be demonstrated to achieve cell dimensions beyond limit of state-of-art lithographic techniques, thus allowing one to fully exploit the scaling potential of high density memory array.

Prof. Tae-Woo Lee (Dept. of Materials Science and Engineering) and his research team have developed a rapid printing technology for high density and scalable memristor array composed of cross-bar-shaped metal nanowires. The research team, which consists of Prof. Tae-Woo Lee, research professor Wentao Xu, and doctoral student Yeongjun Lee at POSTECH [Pohang University of Science and Technology], Korea, published their findings in Advanced Materials.

A Jan. 28, 2016 POSTECH news release, which originated the news item, expands on the theme,

They applied an emerging technique, electrohydrohynamic nanowire printing (e-NW printing), which directly prints highly-aligned nanowire array on a large scale into the fabrication of microminiature memristors, with cross-bar-shaped conductive Cu nanowires jointed with a nanometer-scale CuxO layer. The metal-oxide-metal structure resistive memory device exhibited excellent electrical performance with reproducible resistive switching behavior.

This simple and fast fabrication process avoids conventional vacuum techniques to significantly reduce the industrial-production cost and time. This method paved the way to the future down-scaling of electronic circuits, since 1D conductors represent a logical way to extreme scaling of data processing devices in the single-digit nanometer scale.

They also succeeded in printing memristor array with various shapes, such as parallel lines with adjustable pitch, grids, and waves which can offer a future stretchable memory for integration into textile to serve as a basic building block for smart fabrics and wearable electronics.

“This technology reduces lead time and cost remarkably compared with existing manufacturing methods of cross-bar-shaped nanowire memory and simplifies its method of construction,” said Prof. Lee. “In particular, this technology will be used as a source technology to realize smart fabric, wearable computers, and textile electronic devices.”

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

[Nanowires:] Simple, Inexpensive, and Rapid Approach to Fabricate Cross-Shaped Memristors Using an Inorganic-Nanowire-Digital-Alignment Technique and a One-Step Reduction Process by Wentao Xu, Yeongjun Lee, Sung-Yong Min, Cheolmin Park, andTae-Woo Lee. Advanced Materials Volume 28, Issue 3 January 20, 2016 Page 591  DOI: 10.1002/adma.201503153 Article first published online: 20 NOV 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Memristor shakeup

New discoveries suggest that memristors do not function as was previously theorized. (For anyone who wants a memristor description, there’s this Wikipedia entry.) From an Oct. 13, 2015 posting by Alexander Hellemans for the Nanoclast blog (on the IEEE [Institute for Electrical and Electronics Engineers]), Note: Links have been removed,

What’s going to replace flash? The R&D arms of several companies including Hewlett Packard, Intel, and Samsung think the answer might be memristors (also called resistive RAM, ReRAM, or RRAM). These devices have a chance at unseating the non-volatile memory champion because, they use little energy, are very fast, and retain data without requiring power. However, new research indicates that they don’t work in quite the way we thought they do.

The fundamental mechanism at the heart of how a memristor works is something called an “imperfect point contact,” which was predicted in 1971, long before anybody had built working devices. When voltage is applied to a memristor cell, it reduces the resistance across the device. This change in resistance can be read out by applying another, smaller voltage. By inverting the voltage, the resistance of the device is returned to its initial value, that is, the stored information is erased.

Over the last decade researchers have produced two commercially promising types of memristors: electrochemical metallization memory (ECM) cells, and valence change mechanism memory (VCM) cells.

Now international research teams lead by Ilia Valov at the Peter Grünberg Institute in Jülich, Germany, report in Nature Nanotechnology and Advanced Materials that they have identified new processes that erase many of the differences between EMC and VCM cells.

Valov and coworkers in Germany, Japan, Korea, Greece, and the United States started investigating memristors that had a tantalum oxide electrolyte and an active tantalum electrode. “Our studies show that these two types of switching mechanisms in fact can be bridged, and we don’t have a purely oxygen type of switching as was believed, but that also positive [metal] ions, originating from the active electrode, are mobile,” explains Valov.

Here are links to and citations for both papers,

Graphene-Modified Interface Controls Transition from VCM to ECM Switching Modes in Ta/TaOx Based Memristive Devices by Michael Lübben, Panagiotis Karakolis, Vassilios Ioannou-Sougleridis, Pascal Normand, Pangiotis Dimitrakis, & Ilia Valov. Advanced Materials DOI: 10.1002/adma.201502574 First published: 10 September 2015

Nanoscale cation motion in TaOx, HfOx and TiOx memristive systems by Anja Wedig, Michael Luebben, Deok-Yong Cho, Marco Moors, Katharina Skaja, Vikas Rana, Tsuyoshi Hasegawa, Kiran K. Adepalli, Bilge Yildiz, Rainer Waser, & Ilia Valov. Nature Nanotechnology (2015) doi:10.1038/nnano.2015.221 Published online 28 September 2015

Both papers are behind paywalls.

Save those coffee grounds, they can be used for fuel storage

A September 1, 2015 news item on Nanowerk features research from Korea that could point the way to using coffee grounds for methane storage (Note: A link has been removed),

Scientists have developed a simple process to treat waste coffee grounds to allow them to store methane. The simple soak and heating process develops a carbon capture nanomaterial with the additional environmental benefits of recycling a waste product.

The results are published today, 03 September 2015, in the journal Nanotechnology (“Activated carbon derived from waste coffee grounds for stable methane storage”). [emphasis mine]

Methane capture and storage provides a double environmental return – it removes a harmful greenhouse gas from the atmosphere that can then be used as a fuel that is cleaner than other fossil fuels.

The process developed by the researchers, based at the Ulsan National Institute of Science and Technology (UNIST), South Korea, involves soaking the waste coffee grounds in sodium hydroxide and heating to 700-900 °C in a furnace. This produced a stable carbon capture material in less than a day – a fraction of the time it takes to produce carbon capture materials.

I wonder if someone meant to embargo this news release as the paper isn’t due to be published until Thurs., Sept. 3, 2015.

In any event, the Institute of Physics (IOP) Sept. 1, 2015 news release on Alpha Galileo and elsewhere is making the rounds. Here’s more from the news release,

“The big thing is we are decreasing the fabrication time and we are using cheap materials,” explains Christian Kemp, an author of the paper now based at Pohang University of Science and Technology, Korea. “The waste material is free compared compared to all the metals and expensive organic chemicals needed in other processes – in my opinion this is a far easier way to go.”

Kemp found inspiration in his cup of coffee whilst discussing an entirely different project with colleagues at UNIST. “We were sitting around drinking coffee and looked at the coffee grounds and thought ‘I wonder if we can use this for methane storage?’” he continues.

The absorbency of coffee grounds may be the key to successful activation of the material for carbon capture. “It seems when we add the sodium hydroxide to form the activated carbon it absorbs everything,” says Kemp. “We were able to take away one step in the normal activation process – the filtering and washing – because the coffee is such a brilliant absorbant.”

The work also demonstrates hydrogen storage at cryogenic temperatures, and the researchers are now keen to develop hydrogen storage in the activated coffee grounds at less extreme temperatures.

Once the paper has been published I will return to add a link to and a citation for it.

ETA Sept. 3, 2015 (It seems I was wrong about the publication date):

Activated carbon derived from waste coffee grounds for stable methane storage by K Christian Kemp, Seung Bin Baek, Wang-Geun Lee, M Meyyappan, and Kwang S Kim. IOP Publishing Ltd • Nanotechnology, Volume 26, Number 38 doi:10.1088/0957-4484/26/38/385602) Published 2 September 2015 • © 2015

This is an open access paper.

Plus, there is a copy of the press release on EurekAlert.

Foldable glass (well, there’s some plastic too)

Michael Berger has written a fascinating Aug. 11, 2015 Nanowerk Spotlight article on folding glass,

Have you ever heard about foldable glass?

Exactly.

Glass is notorious for its brittleness. Although industry has developed ultra-thin (∼0.1 mm), flexible glass (like Corning’s Willow® Glass) that can be bent for applications liked curved TV and smartphone displays, fully foldable glass had not been demonstrated. Until now.

Khang [Dahl-Young Khang, an Associate Professor in the Department of Materials Science and Engineering at Yonsei University] and his group have now demonstrated substrate platforms of glass and plastics, which can be reversibly and repeatedly foldable at pre designed location(s) without any mechanical failure or deterioration in device performances.

“We have engineered the substrates to have thinned parts on which the folding deformation should occur,” Moon Jong Han, first author of the paper a graduate student in Khang’s lab, says. “This localizes the deformation strain on those thinned parts only.”

He adds that this approach to engineering substrates has another advantage regarding device materials: “There is no need to adopt any novel materials such as nanowires, carbon nanotubes, graphene, etc. Rather, all the conventional materials that have been used for high-performance devices can be directly applied on our engineered substrates.”

Intriguingly, even ITO (indium tin oxide), a very brittle transparent conducting oxide, can be used as electrode on this novel foldable glass platform.

What makes the approach especially intriguing is the ability to reverse the fold and that it doesn’t require special nanomaterials, such as carbon nanotubes, etc. From Berger’s Aug. 11, 2015 article,

The width of the thinned parts, the gap width, plays the key role in implementing dual foldability. The other key element is the asymmetric design of the gap width for the second folding.

The researchers achieved foldability, in part, by copying a technique used for folding mats and oriental hinge-less screens which have thinned areas to allow folding.

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

Glass and Plastics Platforms for Foldable Electronics and Displays by Moon Jung Han and Dahl-Young Khang. Advanced Materials DOI: 10.1002/adma.201501060 First published: 21 July 2015

This paper is behind a paywall.

Berger’s article is not only fascinating, it is also illustrated with some images provided by the researchers.

Canada and some graphene scene tidbits

For a long time It seemed as if every country in the world, except Canada, had some some sort of graphene event. According to a July 16, 2015 news item on Nanotechnology Now, Canada has now stepped up, albeit, in a peculiarly Canadian fashion. First the news,

Mid October [Oct. 14 -16, 2015], the Graphene & 2D Materials Canada 2015 International Conference & Exhibition (www.graphenecanada2015.com) will take place in Montreal (Canada).

I found a July 16, 2015 news release (PDF) announcing the Canadian event on the lead organizer’s (Phantoms Foundation located in Spain) website,

On the second day of the event (15th October, 2015), an Industrial Forum will bring together top industry leaders to discuss recent advances in technology developments and business opportunities in graphene commercialization.
At this stage, the event unveils 38 keynote & invited speakers. On the Industrial Forum 19 of them will present the latest in terms of Energy, Applications, Production and Worldwide Initiatives & Priorities.

Plenary:
Gary Economo (Grafoid Inc., Canada)
Khasha Ghaffarzadeh (IDTechEx, UK)
Shu-Jen Han (IBM T.J. Watson Research Center, USA)
Bor Z. Jang (Angstron Materials, USA)
Seongjun Park (Samsung Advanced Institute of Technology (SAIT), Korea)
Chun-Yun Sung (Lockheed Martin, USA)

Parallel Sessions:
Gordon Chiu (Grafoid Inc., Canada)
Jesus de la Fuente (Graphenea, Spain)
Mark Gallerneault (ALCERECO Inc., Canada)
Ray Gibbs (Haydale Graphene Industries, UK)
Masataka Hasegawa (AIST, Japan)
Byung Hee Hong (SNU & Graphene Square, Korea)
Tony Ling (Jestico + Whiles, UK)
Carla Miner (SDTC, Canada)
Gregory Pognon (THALES Research & Technology, France)
Elena Polyakova (Graphene Laboratories Inc, USA)
Federico Rosei (INRS–EMT, Université du Québec, Canada)
Aiping Yu (University of Waterloo, Canada)
Hua Zhang (MSE-NTU, Singapore)

Apart from the industrial forum, several industry-related activities will be organized:
– Extensive thematic workshops in parallel (Standardization, Materials & Devices Characterization, Bio & Health and Electronic Devices)
– An exhibition carried out with the latest graphene trends (Grafoid, RAYMOR NanoIntegris, Nanomagnetics Instruments, ICEX and Xerox Research Centre of Canada (XRCC) already confirmed)
– B2B meetings to foster technical cooperation in the field of Graphene

It’s still possible to contribute to the event with an oral presentation. The call for abstracts is open until July, 20 [2015]. [emphasis mine]

Graphene Canada 2015 is already supported by Canada’s leading graphene applications developer, Grafoid Inc., Tourisme Montréal and Université de Montréal.

This is what makes the event peculiarly Canadian: multiculturalism, anyone? From the news release,

Organisers: Phantoms Foundation www.phantomsnet.net & Grafoid Foundation (lead organizers)

CEMES/CNRS (France) | Grafoid (Canada) | Catalan Institute of Nanoscience and Nanotechnology – ICN2 (Spain) | IIT (Italy) | McGill University, Canada | Texas Instruments (USA) | Université Catholique de Louvain (Belgium) | Université de Montreal, Canada

It’s billed as a ‘Canada Graphene 2015’ and, as I recall, these types of events don’t usually have so many other countries listed as organizers. For example, UK Graphene 2015 would have mostly or all of its organizers (especially the leads) located in the UK.

Getting to the Canadian content, I wrote about Grafoid at length tracking some of its relationships to companies it owns, a business deal with Hydro Québec, and a partnership with the University of Waterloo, and a nonrepayable grant from the Canadian federal government (Sustainable Development Technology Canada [SDTC]) in a Feb. 23, 2015 posting. Do take a look at the post if you’re curious about the heavily interlinked nature of the Canadian graphene scene and take another look at the list of speakers and their agencies (Mark Gallerneault of ALCERECO [partially owned by Grafoid], Carla Miner of SDTC [Grafoid received monies from the Canadian federal department],  Federico Rosei of INRS–EMT, Université du Québec [another Quebec link], Aiping Yu, University of Waterloo [an academic partner to Grafoid]). The Canadian graphene community is a small one so it’s not surprising there are links between the Canadian speakers but it does seem odd that Lomiko Metals is not represented here. Still, new speakers have been announced since the news release (e.g., Frank Koppens of ICFO, Spain, and Vladimir Falko of Lancaster University, UK) so  time remains.

Meanwhile, Lomiko Metals has announced in a July 17, 2015 news item on Azonano that Graphene 3D labs has changed the percentage of its outstanding shares affecting the percentage that Lomiko owns, amid some production and distribution announcements. The bit about launching commercial sales of its graphene filament seems more interesting to me,

On March 16, 2015 Graphene 3D Lab (TSXV:GGG) (OTCQB:GPHBF) announced that it launched commercial sales of its Conductive Graphene Filament for 3D printing. The filament incorporates highly conductive proprietary nano-carbon materials to enhance the properties of PLA, a widely used thermoplastic material for 3D printing; therefore, the filament is compatible with most commercially available 3D printers. The conductive filament can be used to print conductive traces (similar to as used in circuit boards) within 3D printed parts for electronics.

So, that’s all I’ve got for Canada’s graphene scene.

Removing poison from cigarette smoke

Here’s what the air/smoke cleaner looks like,

Caption: This is a picture of a prototype of the air cleaning equipment for cigarette smoke installed in an actual smoking room. Credit: ©KIST

Caption: This is a picture of a prototype of the air cleaning equipment for cigarette smoke installed in an actual smoking room.
Credit: ©KIST

A July 8, 3025 ScienceDaily news item provides more details about the air cleaner,

The research team led by Dr. Jongsoo Jurng and Dr. Gwi-Nam at KIST stated that, “In cooperation with KT&G [Korea Tobacco & Ginseng Corporation], KIST [Korea Insitute of Science and Technology) has developed a nano-catalyst filter coated with a manganese oxide-based nano-catalyst, which can be used in a smoking room to reduce and purify major harmful substances of cigarette smoke. the KIST-developed catalyst removes 100% of the particle substances of cigarette smoke, such as nicotine and tar, converting those into water vapor and carbon dioxide. According to the research team, the air cleaning equipment based on the newly-developed catalyst can purify over 80% of the cigarette smoke within 30 minutes and 100% of it within 1 hour in a 30 square meter smoking room, where 10 people are simultaneously smoking

A July 8, 2015 KIST press release (also on EurekAlert), which originated the news item, describes how most air cleaners work to remove smoke and how this new technology differs,

Activated charcoal-based filters have been mostly used in a smoking room to remove gaseous materials in cigarette smoke. However, those filters are not effective in removing gaseous materials such as acetaldehyde, their absorbtion performance decreases fast in a closed facility such as a smoking room, and they need to be replaced at least every other week, which is rather inconvenient.

The research team has developed a nano-catalyst filter by evenly coating a manganese oxide-based (Mn/TiO2)) nano-catalyst powder onto a ceramic-based filter media. The nano-catalyst filter uses a technology that decomposes elements of cigarette smoke using oxygen radical, which is generated by decomposing ozone in the air on the surface of the manganese-oxide-based nano-catalyst filter. An evaluation test with total volatile organic compounds (TVOC), such as acetaldehyde, nicotine and tar, which account for the largest volume of gaseous materials in cigarette smoke, is conducted to evaluate the performance of the newly-developed catalyst. The results show that the new catalyst decomposes over 98% of the aforementioned harmful substances (refer to Fig. 3).

For the performance evaluation test, the research team made an air cleaning equipment prototype using the nano-catalyst filter. The equipment was installed in an actual smoking room in the size of 30 square meters (with processing capacity of 4 CMM [cubic metres per minute]). About 80% of cigarette smoke elements were processed and decomposed to water vapor and carbon dioxide, within 30 minutes, and 100% of them within 1 hour. The test condition was designed based on the processing capacity which could circulate the air inside the entire 30 square meter smoking room once every 15 minutes.

The research team expected that it would take a year or so to commercialize this technology as the nano-catalyst and the filter coating technologies had been developed already.

The lead researcher Dr. Jurng mentioned that “this research holds a significance since the new air cleaning equipment based on a simple catalyst successfully processes and removes gaseous materials in cigarette smoke, which are not easily removed with the existing air cleaning technologies. If the new equipment can be simplified and is economically feasible, it will be an important tool for keeping smoking room pleasant and clean. Also, from the convergence perspective, the new nanometer catalyst filter can be integrated with other air cleaning products such as air purifiers and air conditioners.”

Research overview

Ozone (O3) decomposition method using a catalyst can be utilized as a permanent decomposition technology. When O3 interacts with a metal oxide (Mn/TiO2), O3 is decomposed by the following reactivity formula on the surface of manganese (See Figure 1), generating reactive oxygen species, i.e., oxygen radical. The right side of Figure 1 shows the oxidation process of acetaldehyde (CH3CHO), a substance that accounts for the biggest portion of gaseous materials in cigarette smoke. Acetaldehyde is oxidized and turns into innocuous CO2 and H2O by reactive oxygen species generated in the O3 decomposition process. Other VOCs go through similar oxidation reaction.

The performance of the newly developed catalyst (Mn/TiO2) was evaluated using testing devices at the research lab. The decomposition performance was 98% at maximum in the range from low concentration (10ppm) to high concentration (200ppm). Ozone, which was used for processing reaction, was not discharged or detected after the decomposition reaction as it was completely decomposed by the catalyst.

The air cleaning equipment based on the present technology can be used to clean up cigarette smoke in smoking rooms, etc., and can be utilized in various products such as air conditioners and air purifiers. Also, the technology has great potential and values as it can be converged with other technologies.

###

Glossary of terms

1. Catalytic oxidation and oxygen radical

Catalytic oxidation is known to have high efficiency to oxidize and convert organic substances into innocuous final oxides such as CO2 and H2O. Particularly, with a manganese (Mn)-based catalyst, ozone is decomposed to produce oxygen radical as a reaction intermediate. The oxygen radical is a chemically reactive molecule, which includes oxygen atoms. It has high oxidizing power with high reactivity, and is reported to be effective to process pollutants in the air. Oxygen radicals that fail to react with pollutants are joined together after reaction and are converted to innocuous oxygen (O2) before being discharged into the surrounding.

2. Oxygen radical

Oxygen radical is an oxygen atom in the atomic state prior to being combined into a molecule.

3. Total volatile organic compounds (TVOC)

Total volatile organic compounds (TVOC) is a comprehensive term referring to liquid or gas phase organic compounds that are vaporized into the air at the room temperature. TVOC is known as a carcinogen that can cause disability in the nervous system from skin contact or from inhalation through respiratory organs.

For anyone interested in the diagrams/figures mentioned in the press release, please click the link, July 8, 2015 KIST press release.

Final comment: I love the fact that some of the Korean institutions are including glossaries with their press releases. Thank you!