Category Archives: environment

Light emitting diodes (LEDs) from food and beverage waste

It’s exciting to think that with emerging technologies we’ll be able to make use of waste products rather than sending them off to fill up garbage dumps. An Oct. 13, 2015 news item on Nanowerk highlights some research where food and beverage waste products could be used to produce light emitting diodes (LEDs),

Most Christmas lights, DVD players, televisions and flashlights have one thing in common: they’re made with light emitting diodes (LEDs). LEDs are widely used for a variety of applications and have been a popular, more efficient alternative to fluorescent and incandescent bulbs for the past few decades. Two University of Utah researchers have now found a way to create LEDs from food and beverage waste. In addition to utilizing food and beverage waste that would otherwise decompose and be of no use, this development can also reduce potentially harmful waste from LEDs generally made from toxic elements.

An Oct. 13, 2015 University of Utah news release, which originated the news item, describes some of the issues with our current LEDs and how the researchers went about synthesizing the waste for reuse,

LEDs can be produced by using quantum dots, or tiny crystals that have luminescent properties, to produce light. Quantum dots (QDs) can be made with numerous materials, some of which are rare and expensive to synthesize, and even potentially harmful to dispose of. Some research over the past 10 years has focused on using carbon dots (CDs), or simply QDs made of carbon, to create LEDs instead.

Compared to other types of quantum dots, CDs have lower toxicity and better biocompatibility, meaning they can be used in a broader variety of applications.

U Metallurgical Engineering Research Assistant Professor Prashant Sarswat and Professor Michael Free, over the past year and a half, have successfully turned food waste such as discarded pieces of tortilla into CDs, and subsequently, LEDs.

From bread to bulb

To synthesize waste into CDs, Sarswat and Free employed a solvothermal synthesis, or one in which the waste was placed into a solvent under pressure and high temperature until CDs were formed. In this experiment, the researchers used soft drinks and pieces of bread and tortilla.

The food and beverage waste were each placed in a solvent and heated both directly and indirectly for anywhere from 30 to 90 minutes.

After successfully finding traces of CDs from the synthesis, Sarswat and Free proceeded to illuminate the CDs to monitor their formation and color.

The pair also employed four other tests, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, Raman and AFM [atomic force microscopy] imaging to determine the CDs’ various optical and material properties.

“Synthesizing and characterizing CDs derived from waste is a very challenging task. We essentially have to determine the size of dots which are only 20 nanometers or smaller in diameter, so we have to run multiple tests to be sure CDs are present and to determine what optical properties they possess,” said Sarswat.

For comparison, a human hair is around 75,000 nanometers in diameter.

The various tests Sarswat and Free ran first measured the size of the CDs, which correlates with the intensity of the dots’ color and brightness. The tests then determined which carbon source produced the best CDs. For example, sucrose and D-fructose dissolved in soft drinks were found to be the most effective sources for production of CDs.

An environmentally sustainable alternative

Currently, one of the most common sources of QDs is cadmium selenide, a compound comprised of a two toxic elements. The ability to create QDs in the form of CDs from food and beverage waste would eliminate the need for concern over toxic waste, as the food and beverages themselves are not toxic.

“QDs derived from food and beverage waste are not based on common toxic elements such as cadmium and selenium, which makes their processing and disposal more environmentally friendly than it is for most other QDs.  In addition, the use of food and beverage waste as the starting material for QDs allows for reduced waste and cost to produce a useful material,” said Free.

In addition to being toxic when broken down, cadmium selenide is also expensive—one website listed a price of $529 for 25 ml of the compound.

“With food and beverage waste that are already there, our starting material is much less expensive. In fact, it’s essentially free,” said Sarswat.

According to a report from the US Department of Agriculture, roughly 31% of food produced in 2014 was not available for human consumption. To be able to use this waste for creating LEDs which are widely used in a number of technologies would be an environmentally sustainable approach.

Looking forward, Sarswat and Free hope to continue studying the LEDs produced from food and beverage waste for stability and long term performance.

“The ultimate goal is to do this on a mass scale and to use these LEDs in everyday devices. To successfully make use of waste that already exists, that’s the end goal,” said Sarswat.

Finally, the CDs were suspended in epoxy resins, heated and hardened to solidify the CDs for practical use in LEDs.

The researchers have made an image of the luminescent carbon dots available,

PHOTO CREDIT: Prashant Sarswat The luminescence of carbon dots can be seen when irradiated with UV light.

PHOTO CREDIT: Prashant Sarswat The luminescence of carbon dots can be seen when irradiated with UV light.

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

Light emitting diodes based on carbon dots derived from food, beverage, and combustion wastes by Prashant K. Sarswat and Michael L. Free. Phys. Chem. Chem. Phys., 2015,17, 27642-27652 DOI: 10.1039/C5CP04782J First published online 01 Oct 2015

This paper appears to be behind a paywall. One final note, despite the paper’s title there doesn’t seem to be any mention of combustion waste in the news release which is a bit puzzling.

Smaller (20nm vs 110nm) silver nanoparticles are more likely to absorbed by fish

An Oct. 8, 2015 news item on Nanowerk offers some context for why researchers at the University of California at Los Angeles (UCLA) are studying silver nanoparticles and their entry into the water system,

More than 2,000 consumer products today contain nanoparticles — particles so small that they are measured in billionths of a meter.

Manufacturers use nanoparticles to help sunscreen work better against the sun’s rays and to make athletic apparel better at wicking moisture away from the body, among many other purposes.

Of those products, 462 — ranging from toothpaste to yoga mats — contain nanoparticles made from silver, which are used for their ability to kill bacteria. But that benefit might be coming at a cost to the environment. In many cases, simply using the products as intended causes silver nanoparticles to wind up in rivers and other bodies of water, where they can be ingested by fish and interact with other marine life.

For scientists, a key question has been to what extent organisms retain those particles and what effects they might have.

I’d like to know where they got those numbers “… 2,000 consumer products …” and “… 462 — ranging from toothpaste to yoga mats — contain nanoparticles made from silver… .”

Getting back to the research, an Oct. 7, 2015 UCLA news release, which originated the news item, describes the work in more detail,

A new study by the University of California Center for Environmental Implications of Nanotechnology has found that smaller silver nanoparticles were more likely to enter fish’s bodies, and that they persisted longer than larger silver nanoparticles or fluid silver nitrate. The study, published online in the journal ACS Nano, was led by UCLA postdoctoral scholars Olivia Osborne and Sijie Lin, and Andre Nel, director of UCLA’s Center for Environmental Implications of Nanotechnology and associate director of the California NanoSystems Institute at UCLA.

Nel said that although it is not yet known whether silver nanoparticles are harmful, the research team wanted to first identify whether they were even being absorbed by fish. CEIN, which is funded by the National Science Foundation, is focused on studying the effects of nanotechnology on the environment.

In the study, researchers placed zebrafish in water that contained fluid silver nitrate and two sizes of silver nanoparticles — some measuring 20 nanometers in diameter and others 110 nanometers. Although the difference in size between these two particles is so minute that it can only be seen using high-powered transmission electron microscopes, the researchers found that the two sizes of particles affected the fish very differently.

The researchers used zebrafish in the study because they have some genetic similarities to humans, their embryos and larvae are transparent (which makes them easier to observe). In addition, they tend to absorb chemicals and other substances from water.

Osborne said the team focused its research on the fish’s gills and intestines because they are the organs most susceptible to silver exposure.

“The gills showed a significantly higher silver content for the 20-nanometer than the 110-nanometer particles, while the values were more similar in the intestines,” she said, adding that both sizes of the silver particles were retained in the intestines even after the fish spent seven days in clean water. “The most interesting revelation was that the difference in size of only 90 nanometers made such a striking difference in the particles’ demeanor in the gills and intestines.”

The experiment was one of the most comprehensive in vivo studies to date on silver nanoparticles, as well as the first to compare silver nanoparticle toxicity by extent of organ penetration and duration with different-sized particles, and the first to demonstrate a mechanism for the differences.

Osborne said the results seem to indicate that smaller particles penetrated deeper into the fishes’ organs and stayed there longer because they dissolve faster than the larger particles and are more readily absorbed by the fish.

Lin said the results indicate that companies using silver nanoparticles have to strike a balance that recognizes their benefits and their potential as a pollutant. Using slightly larger nanoparticles might help make them somewhat safer, for example, but it also might make the products in which they’re used less effective.

He added that data from the study could be translated to understand how other nanoparticles could be used in more environmentally sustainable ways.

Nel said the team’s next step is to determine whether silver particles are potentially harmful. “Our research will continue in earnest to determine what the long-term effects of this exposure can be,” he said.

Here’s an image illustrating the findings,

Courtesy ACS Nano

Courtesy ACS Nano

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

Organ-Specific and Size-Dependent Ag Nanoparticle Toxicity in Gills and Intestines of Adult Zebrafish by Olivia J. Osborne, Sijie Lin, Chong Hyun Chang, Zhaoxia Ji, Xuechen Yu, Xiang Wang, Shuo Lin, Tian Xia, and André E. Nel. ACS Nano, Article ASAP DOI: 10.1021/acsnano.5b04583 Publication Date (Web): September 1, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

Anyone have a spare portabella (also known as, portobello) mushroom? I need for my phone

Scientists as the University of California at Riverside (UCR) have developed a type of lithium-ion battery with portabella mushrooms, from a Sept. 29, 2015 news item on ScienceDaily,

Can portabella mushrooms stop cell phone batteries from degrading over time?

Researchers at the University of California, Riverside Bourns College of Engineering think so.

They have created a new type of lithium-ion battery anode using portabella mushrooms, which are inexpensive, environmentally friendly and easy to produce. The current industry standard for rechargeable lithium-ion battery anodes is synthetic graphite, which comes with a high cost of manufacturing because it requires tedious purification and preparation processes that are also harmful to the environment.

A Sept. 29, 2015 UCR news release (also on EurekAlert) by Sean Nealon, which originated the news item, expands on the theme,

With the anticipated increase in batteries needed for electric vehicles and electronics, a cheaper and sustainable source to replace graphite is needed. Using biomass, a biological material from living or recently living organisms, as a replacement for graphite, has drawn recent attention because of its high carbon content, low cost and environmental friendliness.

UC Riverside engineers were drawn to using mushrooms as a form of biomass because past research has established they are highly porous, meaning they have a lot of small spaces for liquid or air to pass through. That porosity is important for batteries because it creates more space for the storage and transfer of energy, a critical component to improving battery performance.

In addition, the high potassium salt concentration in mushrooms allows for increased electrolyte-active material over time by activating more pores, gradually increasing its capacity.

A conventional anode allows lithium to fully access most of the material during the first few cycles and capacity fades from electrode damage occurs from that point on. The mushroom carbon anode technology could, with optimization, replace graphite anodes. It also provides a binderless and current-collector free approach to anode fabrication.

“With battery materials like this, future cell phones may see an increase in run time after many uses, rather than a decrease, due to apparent activation of blind pores within the carbon architectures as the cell charges and discharges over time,” said Brennan Campbell, a graduate student in the Materials Science and Engineering program at UC Riverside.

Nanocarbon architectures derived from biological materials such as mushrooms can be considered a green and sustainable alternative to graphite-based anodes, said Cengiz Ozkan, a professor of mechanical engineering and materials science and engineering.

The nano-ribbon-like architectures transform upon heat treatment into an interconnected porous network architecture which is important for battery electrodes because such architectures possess a very large surface area for the storage of energy, a critical component to improving battery performance.

One of the problems with conventional carbons, such as graphite, is that they are typically prepared with chemicals such as acids and activated by bases that are not environmentally friendly, said Mihri Ozkan, a professor of electrical and computer engineering. Therefore, the UC Riverside team is focused on naturally-derived carbons, such as the skin of the caps of portabella mushrooms, for making batteries.

It is expected that nearly 900,000 tons of natural raw graphite would be needed for anode fabrication for nearly six million electric vehicle forecast to be built by 2020. This requires that the graphite be treated with harsh chemicals, including hydrofluoric and sulfuric acids, a process that creates large quantities of hazardous waste. The European Union projects this process will be unsustainable in the future.

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

Hierarchically Porous Carbon Anodes for Li-ion Batteries by Brennan Campbell, Robert Ionescu, Zachary Favors, Cengiz S. Ozkan, & Mihrimah Ozkan. [Nature] Scientific Reports 5, Article number: 14575 (2015)  doi:10.1038/srep14575 Published online: 29 September 2015

This is an open access paper

Brown University (US) gets big bucks to study effect on nanomaterials on human health

In over seven years of blogging about nanotechnology, this is the most active funding period for health and environmental effects impacts I’ve seen yet. A Sept. 26, 2015 news item on Azonano features another such grant,

With a new federal grant of nearly $10.8 million over the next five years, Brown University researchers and students in the Superfund Research Program (SRP) will be able to advance their work studying how toxicant exposures affect health, how such exposures occur, how nanotechnologies could contain contamination, and how to make sure those technologies are safe.

A Sept. 24, 2015 Brown University news release, which originated the news item, describes of Brown’s SRP work already underway and how this new grant will support it,

“There is more research to be performed,” said Kim Boekelheide, program director, professor of pathology and laboratory medicine, and fellow of the Institute at Brown for Environment and Society (IBES). “Our scientific theme is integrated biomedical and engineering solutions to regulatory uncertainty, using interdisciplinary approaches to attack the really difficult contamination problems that matter.”

The program is pursuing four integrated projects. In one led by Boekelheide, a team is looking at the physiological effects of exposure to toxicants like trichloroethylene on the male reproductive system. In particular he hopes to find the subtle differences in biomolecular markers in sperm that could allow for very early detection of exposure. Meanwhile in another line of research, Eric Suuberg, professor of engineering, is studying how vapors from toxic material releases can re-emerge from the soil entering into buildings built at or near the polluted sites — and why it is hard to predict the level of exposure that inhabitants of these buildings may suffer.

In another project, Robert Hurt, an IBES fellow, SRP co-primary investigator and professor of engineering, is studying how graphene, an atomically thin carbon material, can be used to block the release and transport of toxicants to prevent human exposures. Hurt is also collaborating with Agnes Kane, an IBES fellow and chair and professor of pathology and laboratory medicine, who is leading a study of nanomaterial effects on human health, so they can be designed and used safely in environmental and other applications.

The program will also continue the program’s community outreach efforts in which they work and share information with communities near the state’s Superfund-designated and Brownfield contaminated sites. Scott Frickel, an IBES fellow and associate professor of sociology, is the new leader of community engagement. The program also includes a research translation core in which researchers share their findings and expertise with the U.S. Environmental Protection Agency, state agencies, and professionals involved in contamination management and cleanup. A training core provides opportunities for interdisciplinary research, field work, and industry “externships” for graduate students in engineering, pathobiology, and social sciences at Brown.

It’s good to see they are integrating social sciences into this project although I hope they aren’t attempting this move as a means to coopt and/or stifle genuine dissent and disagreement by giving a superficial nod to the social sciences and public engagement  while wending on their merry way.

Cleaning up carbon dioxide pollution in the oceans and elsewhere

I have a mini roundup of items (3) concerning nanotechnology and environmental applications with a special focus on carbon materials.

Carbon-capturing motors

First up, there’s a Sept. 23, 2015 news item on ScienceDaily which describes work with tiny carbon-capturing motors,

Machines that are much smaller than the width of a human hair could one day help clean up carbon dioxide pollution in the oceans. Nanoengineers at the University of California, San Diego have designed enzyme-functionalized micromotors that rapidly zoom around in water, remove carbon dioxide and convert it into a usable solid form.

The proof of concept study represents a promising route to mitigate the buildup of carbon dioxide, a major greenhouse gas in the environment, said researchers. …

A Sept 22, 2015 University of California at San Diego (UCSD) news release by Liezel Labios, which originated the news release, provides more details about the scientists’ hopes and the technology,

“We’re excited about the possibility of using these micromotors to combat ocean acidification and global warming,” said Virendra V. Singh, a postdoctoral scientist in Wang’s [nanoengineering professor and chair Joseph Wang] research group and a co-first author of this study.

In their experiments, nanoengineers demonstrated that the micromotors rapidly decarbonated water solutions that were saturated with carbon dioxide. Within five minutes, the micromotors removed 90 percent of the carbon dioxide from a solution of deionized water. The micromotors were just as effective in a sea water solution and removed 88 percent of the carbon dioxide in the same timeframe.

“In the future, we could potentially use these micromotors as part of a water treatment system, like a water decarbonation plant,” said Kevin Kaufmann, an undergraduate researcher in Wang’s lab and a co-author of the study.

The micromotors are essentially six-micrometer-long tubes that help rapidly convert carbon dioxide into calcium carbonate, a solid mineral found in eggshells, the shells of various marine organisms, calcium supplements and cement. The micromotors have an outer polymer surface that holds the enzyme carbonic anhydrase, which speeds up the reaction between carbon dioxide and water to form bicarbonate. Calcium chloride, which is added to the water solutions, helps convert bicarbonate to calcium carbonate.

The fast and continuous motion of the micromotors in solution makes the micromotors extremely efficient at removing carbon dioxide from water, said researchers. The team explained that the micromotors’ autonomous movement induces efficient solution mixing, leading to faster carbon dioxide conversion. To fuel the micromotors in water, researchers added hydrogen peroxide, which reacts with the inner platinum surface of the micromotors to generate a stream of oxygen gas bubbles that propel the micromotors around. When released in water solutions containing as little as two to four percent hydrogen peroxide, the micromotors reached speeds of more than 100 micrometers per second.

However, the use of hydrogen peroxide as the micromotor fuel is a drawback because it is an extra additive and requires the use of expensive platinum materials to build the micromotors. As a next step, researchers are planning to make carbon-capturing micromotors that can be propelled by water.

“If the micromotors can use the environment as fuel, they will be more scalable, environmentally friendly and less expensive,” said Kaufmann.

The researchers have provided an image which illustrates the carbon-capturing motors in action,

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

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

Micromotor-Based Biomimetic Carbon Dioxide Sequestration: Towards Mobile Microscrubbers by Murat Uygun, Virendra V. Singh, Kevin Kaufmann, Deniz A. Uygun, Severina D. S. de Oliveira, and oseph Wang. Angewandte Chemie DOI: 10.1002/ange.201505155 Article first published online: 4 SEP 2015

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

This article is behind a paywall.

Carbon nanotubes for carbon dioxide capture (carbon capture)

In a Sept. 22, 2015 posting by Dexter Johnson on his Nanoclast blog (located on the IEEE [Institute for Electrical and Electronics Engineers] website) describes research where carbon nanotubes are being used for carbon capture,

Now researchers at Technische Universität Darmstadt in Germany and the Indian Institute of Technology Kanpur have found that they can tailor the gas adsorption properties of vertically aligned carbon nanotubes (VACNTs) by altering their thickness, height, and the distance between them.

“These parameters are fundamental for ‘tuning’ the hierarchical pore structure of the VACNTs,” explained Mahshid Rahimi and Deepu Babu, doctoral students at the Technische Universität Darmstadt who were the paper’s lead authors, in a press release. “This hierarchy effect is a crucial factor for getting high-adsorption capacities as well as mass transport into the nanostructure. Surprisingly, from theory and by experiment, we found that the distance between nanotubes plays a much larger role in gas adsorption than the tube diameter does.”

Dexter provides a good and brief summary of the research.

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

Double-walled carbon nanotube array for CO2 and SO2 adsorption by Mahshid Rahimi, Deepu J. Babu, Jayant K. Singh, Yong-Biao Yang, Jörg J. Schneider, and Florian Müller-Plathe. J. Chem. Phys. 143, 124701 (2015); http://dx.doi.org/10.1063/1.4929609

This paper is open access.

The market for nanotechnology-enabled environmental applications

Coincident with stumbling across these two possible capture solutions, I found this Sept. 23, 2015 BCC Research news release,

A groundswell of global support for developing nanotechnology as a pollution remediation technique will continue for the foreseeable future. BCC Research reveals in its new report that this key driver, along with increasing worldwide concerns over removing pollutants and developing alternative energy sources, will drive growth in the nanotechnology environmental applications market.

The global nanotechnology market in environmental applications is expected to reach $25.7 billion by 2015 and $41.8 billion by 2020, conforming to a five-year (2015-2020) compound annual growth rate (CAGR) of 10.2%. Air remediation as a segment will reach $10.2 billion and $16.7 billion in 2015 and 2020, respectively, reflecting a five-year CAGR of 10.3%. Water remediation as a segment will grow at a five-year CAGR of 12.4% to reach $10.6 billion in 2020.

As nanoparticles push the limits and capabilities of technology, new and better techniques for pollution control are emerging. Presently, nanotechnology’s greatest potential lies in air pollution remediation.

“Nano filters could be applied to automobile tailpipes and factory smokestacks to separate out contaminants and prevent them from entering the atmosphere. In addition, nano sensors have been developed to sense toxic gas leaks at extremely low concentrations,” says BCC research analyst Aneesh Kumar. “Overall, there is a multitude of promising environmental applications for nanotechnology, with the main focus area on energy and water technologies.”

You can find links to the report, TOC (table of contents), and report overview on the BCC Research Nanotechnology in Environmental Applications: The Global Market report webpage.

A new ink for energy storage devices from the Hong Kong Polytechnic University

Energy storage is not the first thought that leaps to mind when ink is mentioned. Live and learn, eh? A Sept. 23, 2015 news item on Nanowerk describes the connection (Note: A link has been removed),

 The Department of Applied Physics of The Hong Kong Polytechnic University (PolyU) has developed a simple approach to synthesize novel environmentally friendly manganese dioxide ink by using glucose (“Aqueous Manganese Dioxide Ink for Paper-Based Capacitive Energy Storage Devices”).

The MnO2 ink could be used for the production of light, thin, flexible and high performance energy storage devices via ordinary printing or even home-used printers. The capacity of the MnO2 ink supercapacitor is more than 30 times higher than that of a commercial capacitor of the same weight of active material (e.g. carbon powder), demonstrating the great potential of MnO2 ink in significantly enhancing the performances of energy storage devices, whereas its production cost amounts to less than HK$1.

A Sept. 23, 2015 PolyU media release, which originated the news item, expands on the theme,

MnO2 is a kind of environmentally-friendly material and it is degradable. Given the environmental compatibility and high potential capacity of MnO2, it has always been regarded as an ideal candidate for the electrode materials of energy storage devices. The conventional MnO2 electrode preparation methods suffer from high cost, complicated processes and could result in agglomeration of the MnO2 ink during the coating process, leading to the reduction of electrical conductivity. The PolyU research team has developed a simple approach to synthesize aqueous MnO2 ink. Firstly, highly crystalline carbon particles were prepared by microwave hydrothermal method, followed by a morphology transmission mechanism at room temperature. The MnO2 ink can be coated on various substrates, such as conductive paper, plastic and glass. Its thickness and weight can also be controlled for the production of light, thin, transparent and flexible energy storage devices. Substrates coated by MnO2 ink can easily be erased if required, facilitating the fabrication of electronic devices.

PolyU researchers coated the MnO2 ink on conductive A4 paper and fabricated a capacitive energy storage device with maximum energy density and power density amounting to 4 mWh•cm-3 and 13 W•cm-3 respectively. The capacity of the MnO2 ink capacitor is more than 30 times higher than that of a commercial capacitor of the same weight of active material (e.g. carbon powder), demonstrating the great potential of MnO2 ink in significantly enhancing the performances of energy storage devices. Given the small size, light, thin, flexible and high energy capacity properties of the MnO2 ink energy storage device, it shows a potential in wide applications. For instance, in wearable devices and radio-frequency identification systems, the MnO2 ink supercapacitor could be used as the power sources for the flexible and “bendable” display panels, smart textile, smart checkout tags, sensors, luggage tracking tags, etc., thereby contributing to the further development of these two areas.

The related paper has been recently published on Angewandte Chemie International Edition, a leading journal in Chemistry. The research team will work to further improve the performance of the MnO2 ink energy storage device in the coming two years, with special focus on increasing the voltage, optimizing the structure and synthesis process of the device. In addition, further tests will be conducted to integrate the MnO2 ink energy storage device with other energy collection systems.

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

Aqueous Manganese Dioxide Ink for Paper-Based Capacitive Energy Storage Devices by Jiasheng Qian, Huanyu Jin, Dr. Bolei Chen, Mei Lin, Dr. Wei Lu, Dr. Wing Man Tang, Dr. Wei Xiong, Prof. Lai Wa Helen Chan, Prof. Shu Ping Lau, and Dr. Jikang Yuan. Angewandte Chemie International Edition Volume 54, Issue 23, pages 6800–6803, June 1, 2015 DOI: 10.1002/anie.201501261 Article first published online: 17 APR 2015

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

This paper is behind a paywall.

Kavli Foundation roundtable on artificial synthesis as a means to produce clean fuel

A Sept. 9, 2015 news item on Azonano features a recent roundtable discussion about artificial photosynthesis and clean fuel held by the Kavli Foundation,

Imagine creating artificial plants that make gasoline and natural gas using only sunlight. And imagine using those fuels to heat our homes or run our cars without adding any greenhouse gases to the atmosphere. By combining nanoscience and biology, researchers led by scientists at University of California, Berkeley, have taken a big step in that direction.

Peidong Yang, a professor of chemistry at Berkeley and co-director of the school’s Kavli Energy NanoSciences Institute, leads a team that has created an artificial leaf that produces methane, the primary component of natural gas, using a combination of semiconducting nanowires and bacteria. The research, detailed in the online edition of Proceedings of the National Academy of Sciences in August, builds on a similar hybrid system, also recently devised by Yang and his colleagues, that yielded butanol, a component in gasoline, and a variety of biochemical building blocks.

The research is a major advance toward synthetic photosynthesis, a type of solar power based on the ability of plants to transform sunlight, carbon dioxide and water into sugars. Instead of sugars, however, synthetic photosynthesis seeks to produce liquid fuels that can be stored for months or years and distributed through existing energy infrastructure.

In a [Kavli Foundation] roundtable discussion on his recent breakthroughs and the future of synthetic photosynthesis, Yang said his hybrid inorganic/biological systems give researchers new tools to study photosynthesis — and learn its secrets.

There is a list of the participants and an edited transcript of the roundtable, which took place sometime during summer 2015, on the Kavli Foundation’s Fueling up: How nanoscience is creating a new type of solar power webpage (Note: Links have been removed),

The participants were:

PEIDONG YANG – is professor of chemistry and Chan Distinguished Professor of Energy at University of California, Berkeley, and co-director of the Kavli Energy NanoScience Institute at Berkeley National Laboratory and UC Berkeley. He serves as director of the California Research Alliance by BASF, and was a founding member of the U.S. Department of Energy (DOE) Joint Center for Artificial Photosynthesis (JCAP).
THOMAS MOORE – is Regents’ Professor of Chemistry and Biochemistry and past director of the Center for Bioenergy & Photosynthesis at Arizona State University. He is a past president of the American Society for Photobiology, and a team leader at the Center for Bio-Inspired Solar Fuel Production.
TED SARGENT – is a University Professor of Electrical and Computer Engineering at the University of Toronto where he is vice-dean for research for the Faculty of Applied Science and Engineering. He holds the Canada Research Chair in Nanotechnology and is a founder of two companies, InVisage Technologies and Xagenic.

THE KAVLI FOUNDATION (TKF): Solar cells do a good job of converting sunlight into electricity. Converting light into fuel seems far more complicated. Why go through the bother?

THOMAS MOORE: That’s a good question. In order to create sustainable, solar-driven societies, we need a way to store solar energy. With solar cells, we can make electricity efficiently, but we cannot conveniently store that electricity to use when it is cloudy or at night. If we want to stockpile large quantities of energy, we have to store it as chemical energy, the way it is locked up in coal, oil, natural gas, hydrogen and biomass.

PEIDONG YANG: I agree. Perhaps, one day, researchers will come up with an effective battery to store photoelectric energy produced by solar cells. But photosynthesis can solve the energy conversion and storage problem in one step. It converts and stores solar energy in the chemical bonds of organic molecules.

TED SARGENT: Much of the globe’s power infrastructure, from automobiles, trucks and planes to gas-fired electrical generators, is built upon carbon-based fossil fuels. So creating a new technology that can generate liquid fuels that can use this infrastructure is a very powerful competitive advantage for a renewable energy technology.

For someone who’s interested in solar energy and fuel issues, this discussion provide a good introduction to some of what’s driving the research and, happily, none of these scientists are proselytizing.

One final comment. Ted Sargent has been mentioned here several times in connection with his work on solar cells and/or quantum dots.

Natural nanoparticles and perfluorinated compounds in soil

The claim in a Sept. 9, 2015 news item on Nanowerk is that ‘natural’ nanoparticles are being used to remove perfluorinated compounds (PFC) from soil,

Perfluorinated compounds (PFC) are a new type of pollutants found in contaminated soils from industrial sites, airports and other sites worldwide.

In Norway, The Environment Agency has published a plan to eliminate PFOS [perfluorooctanesulfonic acid or perfluorooctane sulfonate] from the environment by 2020. In other countries such as China and the United States, the levels are far higher, and several studies show accumulation of PFOS in fish and animals, however no concrete measures have been taken.

The Norwegian company, Fjordforsk AS, which specializes in nanosciences and environmental methods, has developed a method to remove PFOS from soil by binding them to natural minerals. This method can be used to extract PFOS from contaminated soil and prevent leakage of PFOS to the groundwater.

Electron microscopy images show that the minerals have the ability to bind PFOS on the surface of the natural nanoparticles. [emphasis mine] The proprietary method does not contaminate the treated grounds with chemicals or other parts from remediation process and uses only natural components.

Electron microscopy images and more detail can be found in the Nanowerk news item.

I can’t find the press release, which originated the news item but there is a little additional information about Fjoorkforsk’s remediation efforts on the company’s “Purification of perfluorinated compounds from soil samples” project page,

Project duration: 2014 –

Project leader: Manzetti S.

Collaborators: Prof Lutz Ahrens. Swedish Agricultural University. Prof David van der Spoel, Uppsala University.

Project description:

Perfluorinated compounds (PFCs) are emerging pollutants used in flame retardants on a large scale on airports and other sites of heavy industrial activity. Perfluroinated compounds are toxic and represent an ultra-persistent class of chemicals which can accumulate in animals and humans and have been found to remain in the body for over 5 years after uptake. Perfluorinated compounds can also affect the nerve-system and have recently been associated with high- priority pollutants to be discontinued and to be removed from the environment. Using non-toxic methods, this project develops an approach to sediment perfluorinated compounds from contaminated soil samples using nanoparticles, in order to remove the ecotoxic and ground-water contaminating potential of PFCs from afflicted sites and environments.

The only mineral that I know is used for soil remediation is nano zero-valent iron (nZVI). A very fast search for more information yielded a 2010 EMPA [Swiss Federal Laboratories for Materials Science and Technology] report titled “Nano zero valent iron – THE solution for water and soil remediation? ” (32 pp. pdf) published by ObservatoryNANO.

As for the claim that the company is using ‘natural’ nanoparticles for their remediation efforts, it’s not clear what they mean by that. I suspect they’re using the term ‘natural’ to mean that engineered nanoparticles are being derived from a naturally occurring material, e.g. iron.

Lloyd’s Register and nanotechnology-enabled safety on the high seas, on land, and in the air

On seeing the name Lloyd’s Register and noting the funding is for a university in the UK, Lloyd’s of London, the venerable insurance company leaped to mind. Although there is a connection of sorts, it is somewhat attenuated. First, here’s the news from a Sept. 4, 2015 news item on Azonano,

The University of Southampton has been awarded a multi-million grant from Lloyd’s Register Foundation to bring together some of the world’s brightest early career researchers to find new ways of using nanotechnologies to improve safety at sea, on land and in the air.

A Sept. 3, 2015 University of Southampton press release, which originated the news item, describes plans for the funding,

Dr Themis Prodromakis, from the Nanoelectronics and Nanotechnologies Group at Southampton, is leading the £3m programme, which will receive match funding from partner organisations. He says: “Researchers are always looking for funding for high risk, high reward ideas. They want to collaborate with the best scientists and engineers in the world and gain access to state-of-art facilities. The Lloyd’s Register Foundation International COnsortium in Nanotechnologies (ICON) [Note: This is not to be confused with the now defunct {since Sept. 2014} International Council on Nanotechnology {ICON} at Rice University in Texas, US] will assemble the world’s leading universities, research institutions and innovative companies to help them tackle many of today’s most challenging issues by recruiting talented PhD students from every continent.”

Applications will soon be invited from scientists and engineers keen to pioneer research across a range of industries. Nanotechnologies are already widely used, for example in smart phones, cameras and gadgets. Breakthroughs already being developed include cars, boats and planes built from lightweight materials stronger than steel with new functions such as self-cleaning and repairing; flexible textiles that can become rigid and shockproof to protect the wearer; sensors in hostile environments such as the deep ocean and space; tiny implants for real-time monitoring to aid diagnoses for doctors; and smart devices that harvest energy from their environment.

ICON will support more than 50 PhD students to undertake research at leading global universities, aided by matched funding. They will work together with partners from industry on interdisciplinary projects and access world-leading facilities, such as the £120m Southampton Nanofabrication Centre. The doctoral researchers will meet every year to present their findings and share ideas and concepts, becoming part of a global doctoral cohort addressing the Foundation’s safety mission.

Professor Richard Clegg, Managing Director of Lloyd’s Register Foundation, said: “We are pleased to support the University of Southampton in developing this global cohort of scientists. Their research will develop applications to further the Foundation’s safety goals whilst also providing training and building technical capacity in support of our educational mission. The doctoral students joining this consortium will gain an understanding of how their research can benefit society whilst developing international research networks at an early stage in their careers.”

“The support of Lloyd’s Register Foundation is key to our mission,” adds Dr Prodromakis. “Lloyd’s Register itself is well-known for promoting safety worldwide for more than 250 years. Its Global Technology Centre is now based in Southampton and its Foundation has become a catalyst to support research, training and education for the benefit of society. We are delighted to work alongside them.”

As for the connection between Lloyd’s Register and Lloyd’s of London, let’s start with the Lloyd’s Register Wikipedia entry (Note: Links have been removed),

The organisation’s name came from the 17th-century coffee house in London [emphasis mine] frequented by merchants, marine underwriters, and others, all associated with shipping. The coffee house owner, Edward Lloyd [emphasis mine], helped them to exchange information by circulating a printed sheet of all the news he heard. In 1760, the Register Society was formed by the customers of the coffee house who assembled the Register of Shipping, the first known register of its type. Between 1800 and 1833, a dispute between shipowners and underwriters caused them to publish a list each—the “Red Book” and the “Green Book”.[3] This brought both parties to the verge of bankruptcy. Agreement was reached in 1834 when they united to form Lloyd’s Register of British and Foreign Shipping, establishing a General Committee and charitable values. In 1914, with an increasingly international outlook, the organisation changed its name to Lloyd’s Register of Shipping.

Now here’s what Lloyd’s of London has to say on its History webpage,

In the 17th century, London’s importance as a trade centre led to an increasing demand for ship and cargo insurance. Edward Lloyd’s coffee house [emphasis mine] became recognised as the place for obtaining marine insurance and this is where the Lloyd’s that we know today began.

From those beginnings in a coffee house in 1688, Lloyd’s has been a pioneer in insurance and has grown over 325 years to become the world’s leading market for specialist insurance

Today, Lloyd’s Register describes itself this way (from the Lloyd’s Register homepage),

Lloyd’s Register (LR) is a global engineering, technical and business services organisation wholly owned by the Lloyd’s Register Foundation, a UK charity dedicated to research and education in science and engineering. Founded in 1760 as a marine classification society, LR now operates across many industry sectors, with over 9,000 employees based in 78 countries.

We have a long-standing reputation for integrity, impartiality and technical excellence. Our compliance, risk and technical consultancy services give clients confidence that their assets and businesses are safe, sustainable and dependable. Through our global technology centres and research network, we are at the forefront of understanding the application of new science and technology to future-proof our clients’ businesses.

Well, future-proofing sounds good doesn’t it? It seems like a way of saying you might be able to ‘insure’ yourself against future turmoil.

Center for Sustainable Nanotechnology or how not to poison and make the planet uninhabitable

I received notice of the Center for Sustainable Nanotechnology’s newest deal with the US National Science Foundation in an August 31, 2015 email University of Wisconsin-Madison (UWM) news release,

The Center for Sustainable Nanotechnology, a multi-institutional research center based at the University of Wisconsin-Madison, has inked a new contract with the National Science Foundation (NSF) that will provide nearly $20 million in support over the next five years.

Directed by UW-Madison chemistry Professor Robert Hamers, the center focuses on the molecular mechanisms by which nanoparticles interact with biological systems.

Nanotechnology involves the use of materials at the smallest scale, including the manipulation of individual atoms and molecules. Products that use nanoscale materials range from beer bottles and car wax to solar cells and electric and hybrid car batteries. If you read your books on a Kindle, a semiconducting material manufactured at the nanoscale underpins the high-resolution screen.

While there are already hundreds of products that use nanomaterials in various ways, much remains unknown about how these modern materials and the tiny particles they are composed of interact with the environment and living things.

“The purpose of the center is to explore how we can make sure these nanotechnologies come to fruition with little or no environmental impact,” explains Hamers. “We’re looking at nanoparticles in emerging technologies.”

In addition to UW-Madison, scientists from UW-Milwaukee, the University of Minnesota, the University of Illinois, Northwestern University and the Pacific Northwest National Laboratory have been involved in the center’s first phase of research. Joining the center for the next five-year phase are Tuskegee University, Johns Hopkins University, the University of Iowa, Augsburg College, Georgia Tech and the University of Maryland, Baltimore County.

At UW-Madison, Hamers leads efforts in synthesis and molecular characterization of nanomaterials. soil science Professor Joel Pedersen and chemistry Professor Qiang Cui lead groups exploring the biological and computational aspects of how nanomaterials affect life.

Much remains to be learned about how nanoparticles affect the environment and the multitude of organisms – from bacteria to plants, animals and people – that may be exposed to them.

“Some of the big questions we’re asking are: How is this going to impact bacteria and other organisms in the environment? What do these particles do? How do they interact with organisms?” says Hamers.

For instance, bacteria, the vast majority of which are beneficial or benign organisms, tend to be “sticky” and nanoparticles might cling to the microorganisms and have unintended biological effects.

“There are many different mechanisms by which these particles can do things,” Hamers adds. “The challenge is we don’t know what these nanoparticles do if they’re released into the environment.”

To get at the challenge, Hamers and his UW-Madison colleagues are drilling down to investigate the molecular-level chemical and physical principles that dictate how nanoparticles interact with living things.
Pedersen’s group, for example, is studying the complexities of how nanoparticles interact with cells and, in particular, their surface membranes.

“To enter a cell, a nanoparticle has to interact with a membrane,” notes Pedersen. “The simplest thing that can happen is the particle sticks to the cell. But it might cause toxicity or make a hole in the membrane.”

Pedersen’s group can make model cell membranes in the lab using the same lipids and proteins that are the building blocks of nature’s cells. By exposing the lab-made membranes to nanomaterials now used commercially, Pedersen and his colleagues can see how the membrane-particle interaction unfolds at the molecular level – the scale necessary to begin to understand the biological effects of the particles.

Such studies, Hamers argues, promise a science-based understanding that can help ensure the technology leaves a minimal environmental footprint by identifying issues before they manifest themselves in the manufacturing, use or recycling of products that contain nanotechnology-inspired materials.

To help fulfill that part of the mission, the center has established working relationships with several companies to conduct research on materials in the very early stages of development.

“We’re taking a look-ahead view. We’re trying to get into the technological design cycle,” Hamers says. “The idea is to use scientific understanding to develop a predictive ability to guide technology and guide people who are designing and using these materials.”

What with this initiative and the LCnano Network at Arizona State University (my April 8, 2014 posting; scroll down about 50% of the way), it seems that environmental and health and safety studies of nanomaterials are kicking into a higher gear as commercialization efforts intensify.