Researchers at Melbourne’s RMIT University Convert CO2 back into Coal in Carbon Breakthrough – (Captured) Carbon produced could also be used as an electrode … Watch Video


 

 

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Australian scientists have unlocked a new and more “efficient” way  to turn carbon dioxide back into solid coal, in a world-first breakthrough that could combat rising greenhouse gas levels.

Researchers at Melbourne’s RMIT University have used liquid metals to convert CO2 from a gas to a solid at room temperature.

The technique has potential to “safely and permanently” remove CO2 from the atmosphere, according to the new study published in the journal Nature Communications.

Carbon technologies have previously tended to focus on compressing CO2 into a liquid form, transporting it to a suitable site and injecting it underground.

The use of underground injections to capture and store carbon is not economically viable and sparks fears of an environmental catastrophe due to possible leaks from the storage site.

However, the new technique transforms CO2 into solid flakes of carbon, similar to coal, which can be stored more easily and securely.

Carbon dioxide is dissolved into a beaker containing an electrolyte liquid, then a small amount of the liquid metal catalyst is added, which is then charged with an electrical current.

The electrical current serves as a catalyst to slowly converts the CO2 into solid flakes of carbon.

Watch how researchers made their discovery

This is a “crucial first step” to developing a more sustainable approach to converting CO2 into a solid, RMIT researcher Dr Torben Daeneke said, noting that more research is required cement the process.

He described the process as “efficient and scalable”.

“While we can’t literally turn back time, turning carbon dioxide back into coal and burying it back in the ground is a bit like rewinding the emissions clock.

“To date, CO2 has only been converted into a solid at extremely high temperatures, making it industrially un-viable,” Dr Daeneke said.

The study’s lead author, Dr Dorna Esrafilzadeh, said the carbon produced could also be used as an electrode.

“A side benefit of the process is that the carbon can hold electrical charge, becoming a supercapacitor, so it could potentially be used as a component in future vehicles,” she said.

“The process also produces synthetic fuel as a by-product, which could also have industrial applications.”

The study was completed in collaboration with researchers from Germany (University of Munster), China (Nanjing University of Aeronautics and Astronautics), the US (North Carolina State University) and Australia (UNSW, University of Wollongong, Monash University, QUT).

Learn More About ‘Great Things from Small Things’ ~ Watch A Video on Our Current Project: Nano Enabled Batteries and Super Capacitors

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Smart Grid and Nanotechnologies: How can Nanotechnology Reduce CO2 emissions? A Solution For Clean and Sustainable Energy


Renewable Energy Pix

Environmental sustainability remains a big trend; topics such as climate change and global warming are generating a lot of discussion. Growing world energy demand from fossil fuels plays a key role in the upward trend in CO2 emissions and is the main source of human-induced climate changes. While energy systems around the world remain at vastly different stages of development, all countries share a common problem: they are far away from achieving sustainable energy systems. As levels of CO2 and other greenhouse gases continue to rise in the atmosphere, with historical maximums reached lately, sustainability in energy generation and energy efficiency principles is becoming ever more important.

Introduction

For the first time in recorded history, more people worldwide are living in urban areas than in rural. The urbanization trend picked up pace in the 20th century and has accelerated since. Urbanization manifests itself in two ways: expansion of existing cities and creation of new ones.1 Cities are already the source of close to 80% of global CO2 (carbon-dioxide) emissions and will account for an ever-higher percentage in the coming years.

Too much CO2 in the atmosphere has been linked to climate change. If humanity continued with the same solutions that have been used to address urban development needs in the past, the resulting urban ecological footprint will not be sustainable: we would need the equivalent of two planets to maintain our lifestyles by the 2030s. The challenge is to meet the demands of urbanization in an economically viable, socially inclusive, and environmentally sustainable fashion.1,2

According to a World Energy Council study,3 global demand for primary energy is expected to increase by between 27% and 61% by 2050. Climate change is expected to lead to changes in a range of climatic variables, most notably temperature levels. Since electricity demand is closely influenced by temperature, there is likely to be an impact on power demand patterns. The magnitude of the potential impact of future climate changes on electricity demand will depend on patterns in the power use, as well as long-term socio-economic trends.

The latest assessment by Working Group I of the Intergovernmental Panel on Climate Change, released in September 2013, concluded that climate change remains one of the greatest challenges facing society. Warming of the climate system is unequivocal, human-influenced, and many unprecedented changes have been observed throughout the climate system since 1950. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions.4

Consumption patterns, together with aging and urbanization in some countries seem to have bigger implications for health and the reduction of carbon emissions than the total number of people in the world.5 As developing and newly industrialized countries improve their standards of living, their use of air conditioning and other weather-dependent consumption will likely increase their sensitivity to climate change.6 On the other hand, reducing consumption and achieving more sustainable lifestyles in rich countries will likely represent the most effective way to reduce carbon emissions.

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How can nanotechnology reduce CO2 emission?

“The Grid” and Improving Efficiencies

Nanotechnology is a platform whereby matter is manipulated at the atomic level. There are various ways that nanotechnology can be applied along the Smart Grid to help reduce CO2 emissions.

The major impact of nanotechnology on the energy sector is likely to improve the efficiency of current technologies to minimize use of fossil fuels. Any effort to reduce emissions in vehicles by reducing their weight and, in turn, decreasing fuel consumption can have an immediate and significant global impact.

It is estimated that a 10% reduction in weight of the vehicle corresponds to a 10% reduction in fuel consumption, leading to a proportionate fall in emissions. In recognition of the above, there is growing interest worldwide in exploring means of achieving weight reduction in automobiles through use of novel materials. For example, use of lighter, stronger, and stiffer nano-composite materials is considered to have the potential to significantly reduce vehicle weight.9,49

Nanotechnology is applied in aircraft coatings, which protect the materials from the special conditions of the environment where they are used (instead of the conventional bulk metals such as steel). Since the amount of CO2 emitted by an aircraft engine is directly related to the amount of fuel burned, CO2 can be reduced by making the airplane lighter.

Nanocoatings are one of the options for aerospace developers, but also for automotive, defense, marine, and plastics industries.49 Lufthansa Cargo uses the most advanced technologies and innovative processes including efficient jet engines, nanotechnology in aircraft coatings, new composites or regular jet engine cleaning – and of course monitoring overall aircraft weight. It is often a matter of only a few grams. However, given 15,000 to 16,000 flights a year and an average flight time of about 6 hours, the cumulative effect of a number of grams can quickly add up to tons. The removal of a 350 gram phone handset resulted in jet fuel savings of 3.5 tons in a year.50

Nanotechnology is already applied to improve fuel efficiency by incorporation of nanocatalysts. Enercat, a third generation nanocatalyst developed by Energenics, uses the oxygen storing cerium oxide nanoparticles to promote complete fuel combustion, which helps in reducing fuel consumption. Recently, the company has demonstrated fuel savings of 8%–10% on a mixed fleet of diesel vehicles in Italy.51

Reducing friction and improving wear resistance in engine and drive train components is of vital importance in the automotive sector. Based on the estimates made by a Swedish company Applied Nano Surfaces, reducing friction can lower the fuel consumption by about 2% and result in cutting down CO2 emissions by 500 million tons per year from trucks and other heavy vehicles in Sweden alone.9 Thanks to nanomaterials like silica, many tires will in the future be capable of attaining the best rating, the green category A. Cars equipped with category A tires consume approximately 7.5% less fuel than those with tires of the minimum standard (category G).52

Residential and commercial buildings contribute to 11% of total greenhouse gas emissions. Space heating and cooling of residential buildings account for 40% of the total residential energy use. Nanostructured materials, such as aerogels, have the potential to greatly reduce heat transfer through building elements and assist in reducing heating loads placed on air-conditioning/heating systems. Aerogel is a nanoporous super-insulating material with extremely low density; silica aerogel is the lightest solid material known with excellent thermal insulating properties, high temperature stability, very low dielectric constant and high surface area.51

Nanotechnology is positioned to create significant change across several domains, especially in energy where it may bring large and possibly sudden performance gains to renewable sources and Smart Grids. Nanotech enhancements may also increase battery power by orders of magnitude, allowing intermittent sources such as solar and wind to provide a larger share of overall electricity supply without sacrificing stability. Nanotech sensors will also enable Smart Grids and foster more flexible and decentralized electricity management.53

Nanotechnology may accelerate the technology behind renewables in various ways:

  • experts are discovering means to apply nanotechnology to photovoltaics, which would produce solar panels with double or triple the output by 2020;
  • wind turbines stand to be improved from high-performance nano-materials like graphene, a nano-engineered one-atom thick layer of mineral graphite that is 100 times stronger than steel. Nanotechnology will enable light and stiff wind blades that spin at lower wind speeds than regular blades;
  • nanotechnology could play a major role in the next generation of batteries. For example, coating the surface of an electrode with nanoparticles increases the surface area, thereby allowing more current to flow between the electrode and the chemicals inside the battery. Such techniques could increase the efficiency of electric and hybrid vehicles by significantly reducing the weight of the batteries. Moreover, superior batteries would complement renewables by storing energy economically, thus offsetting the whole issue of intermittent generation.

In a somewhat more distant future, we may see electricity systems apply nanotechnology in transmission lines. Research indicates that it is possible to develop electrical wires using carbon nanotubes that can carry higher loads and transmit without power losses even over hundreds of kilometers. The implications are significant, as it would increase the efficiency of generating power where the source is easiest to harness.53

Semiconductor devices, transistors, and sensors will benefit from nanotechnology especially in size and speed. Nanotech sensors could be used for the Smart Grid to detect issues ahead of time, ie, to measure degrading of underground cables or to bring down the price of chemical sensors already available for transformers. Nanotechnology will likely become indispensable for the Smart Grid to fully evolve in the near future.54

Energy efficiency is a way of managing and restraining the growth of energy consumption. It is one of the easiest and most cost effective ways to combat climate change, improve the competitiveness of businesses, and reduce energy costs for consumers.7

More on Using Nanotechnology to Reduce Carbon-Based Emissions

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Berkley Lab: A Better Way of Scrubbing CO2

Berkeley Lab Researchers Find Way to Improve the Cost-Effectiveness Through the Use of MOFs

A means by which the removal of carbon dioxide (CO2) from coal-fired power plants might one day be done far more efficiently and at far lower costs than today has been discovered by a team of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). By appending a diamine molecule to the sponge-like solid materials known as metal-organic-frameworks (MOFs), the researchers were able to more than triple the CO2-scrubbing capacity of the MOFs, while significantly reducing parasitic energy.

Read the Full Article Here: https://genesisnanotech.wordpress.com/2015/03/17/berkley-lab-a-better-way-of-scrubbing-co2/

Nanotechnology material could help reduce CO2 emissions from coal-fired power plants

1-KAUST Materials gilles-coinsliderUniversity of Adelaide researchers have  developed a new nanomaterial that could help reduce carbon dioxide emissions  from coal-fired power stations.

The new nanomaterial, described in the Journal of the  American Chemical Society (“Post-synthetic Structural Processing in a  Metal–Organic Framework Material as a Mechanism for Exceptional CO2/N2 Selectivity”), efficiently separates the  greenhouse gas carbon dioxide from nitrogen, the other significant component of  the waste gas released by coal-fired power stations. This would allow the carbon  dioxide to be separated before being stored, rather than released to the  atmosphere.
“A considerable amount of Australia‘s – and the world’s – carbon  dioxide emissions come from coal-fired power stations,” says Associate Professor  Christopher Sumby, project leader and ARC Future Fellow in the  University’s School of Chemistry and Physics.

Read the Full Article Here: https://genesisnanotech.wordpress.com/2013/07/10/nanotechnology-material-could-help-reduce-co2-emissions-from-coal-fired-power-plants/

One Nano-Crystal – Many Facets – Reducing Fuel Toxins

cubic CeO2 nanoparticlesWhen it comes to reducing the toxins released by burning gasoline, coal, or other such fuels, the catalyst needs to be reliable. Yet, a promising catalyst, cerium dioxide (CeO2), seemed erratic. The catalyst’s three different surfaces behaved differently. For the first time, researchers got an atomically resolved view of the three structures, including the placement of previously difficult-to-visualize oxygen atoms. This information may provide insights into why the surfaces have distinct catalytic properties (“Probing the Surface Sites of CeO2 Nanocrystals with Well-Defined Surface Planes via Methanol Adsorption and Desorption”).

Read the Full Article Here: https://genesisnanotech.wordpress.com/2015/06/12/one-nano-crystal-many-facets-reducing-fuel-toxins/

Conclusion

This review demonstrates the potential for reduction of CO2 emissions that Smart Grids can potentially achieve. Power grid modernization is an evolution that will continue for years or decades, and providing a robust foundation for new applications and technologies is imperative.

The electric power industry is facing tremendous opportunities and becoming increasingly important in the emerging low-carbon economy. Governments are still dominant players in high-cost smart-grid investments. This suggests the need for a policy framework that attracts private capital investment, especially from renewable project developers, and communication and ICT companies.

The challenge we face is neither a technical nor policy one – it is political: the current pace of action is simply insufficient. The technologies to reduce emission levels to a level consistent with the 2°C target are available and we know which policies we can use to deploy them. However, the political will to do so remains weak. This lack of political will comes with a price: we will have to undertake steeper and more costly actions to potentially bridge the emissions gap by 2020.4 However, technical possibilities aside, the key to reducing emission levels will be the tough but unavoidable decision that reducing carbon pollution must be of the highest priority.

To Read the Full Article Go Here: http://www.dovepress.com/smart-grid-and-nanotechnologies-a-solution-for-clean-and-sustainable-e-peer-reviewed-fulltext-article-EECT

Rice U. Researchers Fine-Tune Quantum Dots from Coal


rice QD finetuneGraphene quantum dots made from coal, introduced in 2013 by the Rice University lab of chemist James Tour, can be engineered for specific semiconducting properties in either of two single-step processes.

In a new study this week in the American Chemical Society journal Applied Materials & Interfaces, Tour and colleagues demonstrated fine control over the graphene oxide dots’ size-dependent band gap, the property that makes them semiconductors. Quantum dots are semiconducting materials that are small enough to exhibit quantum mechanical properties that only appear at the nanoscale.

Tour’s group found they could produce quantum dots with specific semiconducting properties by sorting them through ultrafiltration, a method commonly used in municipal and industrial water filtration and in food production.

The other single-step process involved direct control of the reaction temperature in the oxidation process that reduced coal to quantum dots. The researchers found hotter temperatures produced smaller dots, which had different semiconducting properties.

Tour said graphene quantum dots may prove highly efficient in applications ranging from medical imaging to additions to fabrics and upholstery for brighter and longer-lasting colors. “Quantum dots generally cost about $1 million per kilogram and we can now make them in an inexpensive reaction between coal and acid, followed by separation. And the coal is less than $100 per ton.”

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The dots in these experiments all come from treatment of anthracite, a kind of coal. The processes produce batches in specific sizes between 4.5 and 70 nanometers in diameter.

Rice University scientists have produced graphene quantum dots produced from coal with tuned band gaps and photoluminescent properties. These quantum dots, seen with an electron microscope, average 70 nanometers in diameter. Credit: Tour Group/Rice University

Graphene quantum dots are photoluminescent, which means they emit light of a particular wavelength in response to incoming light of a different wavelength. The emitted light ranges from green (smaller dots) to orange-red (larger dots). Because the emitted color also depends on the dots’ size, this property can also be tuned, Tour said. The lab found quantum dots that emit blue light were easiest to produce from bituminous .

The researchers suggested their quantum dots may also enhance sensing, electronic and photovoltaic applications. For instance, catalytic reactions could be enhanced by manipulating the reactive edges of . Their fluorescence could make them suitable for metal or chemical detection applications by tuning to avoid interference with the target materials’ emissions.

Rice University scientists have produced graphene quantum dots produced from coal with tuned band gaps and photoluminescent properties. These quantum dots are about 4.5 nanometers in diameter. Credit: Tour Group/Rice University

Explore further: Making quantum dots glow brighter

Read more at: http://phys.org/news/2015-03-fine-tune-quantum-dots-coal.html#jCp

Berkley Lab: A Better Way of Scrubbing CO2


Jeff-Long-CO2-New-284x300Berkeley Lab Researchers Find Way to Improve the Cost-Effectiveness Through the Use of MOFs

A means by which the removal of carbon dioxide (CO2) from coal-fired power plants might one day be done far more efficiently and at far lower costs than today has been discovered by a team of researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab). By appending a diamine molecule to the sponge-like solid materials known as metal-organic-frameworks (MOFs), the researchers were able to more than triple the CO2-scrubbing capacity of the MOFs, while significantly reducing parasitic energy.

“We’ve shown that diamine-appended MOFs can function as phase-change CO2 adsorbents, with unusual step-shaped CO2 adsorption isotherms that shift markedly with temperature and result in a much higher separation capacity,” says Jeffrey Long, a chemist with Berkeley Lab’s Materials Sciences Division and the University of California (UC) Berkeley. “The step-shaped adsorption isotherms are the product of an unprecedented cooperative process in which CO2 molecules insert into metal-amine bonds, inducing a reorganization of the amines into well-ordered chains of ammonium carbamate.”

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Appending a diamine molecule to this manganese-based MOF greatly increased its capacity for adsorbing CO2. Green, gray, red, blue and white spheres represent Mn, C, O, N and H atoms respectively.

Details on this research are reported in a paper published in the journal Nature. The paper is titled “Cooperative insertion of CO2 in diamine-appended metal-organic frameworks.” Long is the corresponding author. The lead authors are Thomas McDonald and Jarad Mason. (See below for a complete list of co-authors.)

(From left) Tom McDonald, Jeffrey Long and Jarad Mason were part of a collaboration that discovered a way to improve the carbon-scrubbing capabilities of MOFs. (Photo by Roy Kaltschmidt)

Approximately 13 billion tons of carbon dioxide are released into the atmosphere each year as a result of burning coal for the production of electricity. These carbon emissions are major contributors to global climate change and the acidification of our planet’s oceans. However, given that the United States holds the world’s largest estimated recoverable reserves of coal, coal-burning power plants will continue to be a major source of our nation’s electricity generation for the foreseeable future. This makes the wide-spread implementation of carbon capture and storage technologies at coal-fired power plants an imperative.

Current carbon capture and storage technologies are based on aqueous amine scrubbers that impose a substantial energy penalty for their use. If widely implemented, these scrubbers would consume about one-third of the energy generated by a power plant and this would substantially drive up the price of electricity. MOFs have been proposed as a highly promising alternative to amine scrubbers. Consisting of a metal center surrounded by organic “linker” molecules, MOFs form a highly porous three-dimensional crystal framework with an extraordinarily large internal surface area – a MOF the size of a sugar cube if unfolded and flattened would blanket a football field. By altering their composition, MOFs can be tailored to serve as highly effective storage vessels for capturing and containing carbon dioxide.

Long and colleagues at the Center for Gas Separation Relevant to Clean Energy Technologies, a DOE-funded Energy Frontier Research Center (EFRC) hosted by UC Berkeley, have been exploring various ways to functionalize MOFs for the selective adsorption of CO2.

“An ideal MOF will selectively bind CO2 in the presence of nitrogen and release it under mild regeneration conditions,” Long says. “We were experimenting with the appending of diamines to the open coordination sites in the framework pores of a MOF as a way of increasing the adsorption of CO2. Once we saw the formation of the isotherm steps we knew we had something different and important going on.”

A portion of the ammonium carbamate chain formed along the pore surface of a MOF when CO2 molecules are inserted into metal-amine bonds. Green, gray, red, blue and white spheres represent Mn, C, O, N and H atoms respectively.

The appending of the diamine to the metal sites set off a chain reaction of events in which the carbon, metal and amines cooperatively reconfigured into the ammonium carbonates that enabled the CO2 isotherm adsorption steps. The researchers then found that the pressure at which these adsorption steps occur can be tuned in accordance with the strengths of the metal-amine bonds. By starting with magnesium ions, then strategically replacing them with ions of manganese, iron, cobalt and zinc, Long and his colleagues were able to create the first solid phase-change CO2 scrubbing materials.

“With our technique, large CO2 separation capacities can be achieved with small temperature swings and regeneration energies that are appreciably lower than what can be achieved with state-of-the-art aqueous amine solutions,” Long says. “We now understand how this CO2 cooperative process works and should be able to use the mechanism to design highly efficient adsorbents for removing CO2 from various gas mixtures.”

To adapt this technique to real-world applications, Long is now working with chemist Steven Kaye on the Mosaic Materials Project. Aimed at replacing today’s energy-intensive and expensive distillation and adsorption processes with high-efficiency MOFs, the Mosaic Materials Project is being funded by Cyclotron Road, a technology-incubation program established by Berkeley Lab.

In addition to Long, McDonald and Mason, other authors of the Nature paper that describes this study were Xueqian Kong, Eric  Bloch, David Gygi, Alessandro Dani, Valentina Crocella, Filippo Giordanino, Samuel O. Odoh, Walter Drisdell, Bess Vlaisavljevich, Allison Dzubak, Roberta Poloni, Sondre Schnell, Nora Planas, Kyuho Lee, Tod Pascal, Liwen F.Wan, David Prendergast, Jeffrey Neaton, Berend Smit, Jeffrey Kortright, Laura Gagliardi, Silvia Bordiga and Jeffrey Reimer.

Portions of this research were supported by DOE’s Advanced Research Projects Agency–Energy (ARPA-E).

Additional Information

For more about the research of Jeffrey Long go here

Quantum Dots from a Familiar Energy Source, Coal: Video


201306047919620The prospect of turning coal into fluorescent particles may sound too good to be true, but the possibility exists, thanks to scientists at Rice University.

The Rice lab of chemist James Tour found simple methods to reduce three kinds of coal into graphene quantum dots (GQDs), microscopic discs of atom-thick graphene oxide that could be used in medical imaging as well as sensing, electronic and photovoltaic applications.

Coal yields production of graphene quantum dots

Band gaps determine how a semiconducting material carries an electric current. In quantum dots, band gaps are responsible for their fluorescence and can be tuned by changing the dots’ size. The process by Tour and company allows a measure of control over their size, generally from 2 to 20 nanometers, depending on the source of the coal.

Graphic

An illustration shows the nanostructure of bituminous coal before separation into graphene quantum dots. Courtesy of the Tour Group

There are many ways to make GQDs now, but most are expensive and produce very small quantities, Tour said. Though another Rice lab found a way last year to make GQDs from relatively cheap carbon fiber, coal promises greater quantities of GQDs made even cheaper in one chemical step, he said.

“We wanted to see what’s there in coal that might be interesting, so we put it through a very simple oxidation procedure,” Tour explained. That involved crushing the coal and bathing it in acid solutions to break the bonds that hold the tiny graphene domains together.

“You can’t just take a piece of graphene and easily chop it up this small,” he said.

Tour depended on the lab of Rice chemist and co-author Angel Martí to help characterize the product. It turned out different types of coal produced different types of dots. GQDs were derived from bituminous coalanthracite and coke, a byproduct of oil refining.

Graphene quantum dots

An electron microscope image shows the stacking layer structure of graphene quantum dots extracted from anthracite. The scale bar equals 100 nanometers. Courtesy of the Tour Group.

The coals were each sonicated in nitric and sulfuric acids and heated for 24 hours. Bituminous coal produced GQDs between 2 and 4 nanometers wide. Coke produced GQDs between 4 and 8 nanometers, and anthracite made stacked structures from 18 to 40 nanometers, with small round layers atop larger, thinner layers. (Just to see what would happen, the researchers treated graphite flakes with the same process and got mostly smaller graphite flakes.)

Tour said the dots are water-soluble, and early tests have shown them to be nontoxic. That offers the promise that GQDs may serve as effective antioxidants, he said.

Medical imaging could also benefit greatly, as the dots show robust performance as fluorescent agents.

“One of the problems with standard probes in fluorescent spectroscopy is that when you load them into a cell and hit them with high-powered lasers, you see them for a fraction of a second to upwards of a few seconds, and that’s it,” Martí said. “They’re still there, but they have been photo-bleached. They don’t fluoresce anymore.”

Testing in the Martí lab showed GQDs resist bleaching. After hours of excitation, Martí said, the photoluminescent response of the coal-sourced GQDs was barely affected.

Rice University chemist James Tour, left, and graduate student Ruquan Ye show the source and destination of graphene quantum dots extracted from coal in a process developed at Rice. Tour said the fluorescent particles can be drawn in bulk from coal in a one-step process. Photo by Jeff Fitlow

That could make them suitable for use in living organisms. “Because they’re so stable, they could theoretically make imaging more efficient,” he said.

A small change in the size of a quantum dot – as little as a fraction of a nanometer – changes its fluorescent wavelengths by a measurable factor, and that proved true for the coal-sourced GQDs, Martí said.

Low cost will also be a draw, according to Tour. “Graphite is $2,000 a ton for the best there is, from the U.K.,” he said. “Cheaper graphite is $800 a ton from China. And coal is $10 to $60 a ton.

“Coal is the cheapest material you can get for producing GQDs, and we found we can get a 20 percent yield. So this discovery can really change the quantum dot industry. It’s going to show the world that inside of coal are these very interesting structures that have real value.”

Co-authors of the work include graduate students Ruquan Ye, Changsheng Xiang, Zhiwei Peng, Kewei Huang, Zheng Yan, Nathan Cook, Errol Samuel, Chih-Chau Hwang, Gedeng Ruan, Gabriel Ceriotti and Abdul-Rahman Raji and postdoctoral research associate Jian Lin, all of Rice. Martí is an assistant professor of chemistry and bioengineering. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of mechanical engineering and materials science and of computer science.

The Air Force Office of Scientific Research and the Office of Naval Research funded the work through their Multidisciplinary University Research Initiatives.

For more:  http://news.rice.edu/2013/12/06/coal-…

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