13 Jun 2016
Australian researchers at the University of Adelaide have developed a method for embedding light-emitting nanoparticles into glass without losing any of their unique properties – a major step towards ‘smart glass’ applications such as 3D display screens or remote radiation sensors.
This new “hybrid glass” successfully combines the properties of these special luminescent (or light-emitting) nanoparticles with the well-known aspects of glass, such as transparency and the ability to be processed into various shapes including very fine optical fibres.
The research, in collaboration with Macquarie University and University of Melbourne, has been published online in the journal Advanced Optical Materials.
“These novel luminescent nanoparticles, called upconversion nanoparticles, have become promising candidates for a whole variety of ultra-high tech applications such as biological sensing, biomedical imaging and 3D volumetric displays,” says lead author Dr Tim Zhao, from the University of Adelaide’s School of Physical Sciences and Institute for Photonics and Advanced Sensing (IPAS).
“Integrating these nanoparticles into glass, which is usually inert, opens up exciting possibilities for new hybrid materials and devices that can take advantage of the properties of nanoparticles in ways we haven’t been able to do before. For example, neuroscientists currently use dye injected into the brain and lasers to be able to guide a glass pipette to the site they are interested in. If fluorescent nanoparticles were embedded in the glass pipettes, the unique luminescence of the hybrid glass could act like a torch to guide the pipette directly to the individual neurons of interest.”
Although this method was developed with upconversion nanoparticles, the researchers believe their new ‘direct-doping’ approach can be generalised to other nanoparticles with interesting photonic, electronic and magnetic properties. There will be many applications – depending on the properties of the nanoparticle.
“If we infuse glass with a nanoparticle that is sensitive to radiation and then draw that hybrid glass into a fibre, we could have a remote sensor suitable for nuclear facilities,” says Dr Zhao.
To date, the method used to integrate upconversion nanoparticles into glass has relied on the in-situ growth of the nanoparticles within the glass.
“We’ve seen remarkable progress in this area but the control over the nanoparticles and the glass compositions has been limited, restricting the development of many proposed applications,” says project leader Professor Heike Ebendorff-Heideprem, Deputy Director of IPAS.
“With our new direct doping method, which involves synthesizing the nanoparticles and glass separately and then combining them using the right conditions, we’ve been able to keep the nanoparticles intact and well dispersed throughout the glass. The nanoparticles remain functional and the glass transparency is still very close to its original quality. We are heading towards a whole new world of hybrid glass and devices for light-based technologies.”
Explore further: Ancient Roman glass inspires modern science
More information: Jiangbo Zhao et al. Upconversion Nanocrystal-Doped Glass: A New Paradigm for Photonic Materials, Advanced Optical Materials(2016). DOI: 10.1002/adom.201600296
Large quantities of steel are used in architecture, bridge construction and ship-building. Structures of this type are intended to be long-lasting. Furthermore, even in the course of many years, they must not lose any of their qualities regarding strength and safety. For this reason, the steel plates and girders used must have extensive and durable protection against corrosion. In particular, the steel is attacked by oxygen in the air, water vapor and salts. Nowadays, various techniques are used to prevent the corrosive substances from penetrating into the material. One common method is to create an anti-corrosion coating by applying layers of zinc-phosphate. Now, research scientists at INM — Leibniz Institute for New Materials developed a special type of zinc-phosphate nanoparticles. In contrast to conventional, spheroidal zinc-phosphate nanoparticles, the new nanoparticles are flake-like. They are ten times as long as they are thick. As a result of this anisotropy, the penetration of gas molecules into the metal is slowed down.
The developers will be demonstrating their results and the possibilities they offer at stand B46 in hall 2 at this year’s Hanover Trade Fair as part of the leading trade show Research & Technology which takes place from 25th to 29th April.
“In first test coatings, we were able to demonstrate that the flake-type nanoparticles are deposited in layers on top of each other thus creating a wall-like structure,” explained Carsten Becker-Willinger, Head of Nanomers® at INM. “This means that the penetration of gas molecules through the protective coating is longer because they have to find their way through the ´cracks in the wall´.” The result, he said, was that the corrosion process was much slower than with coatings with spheroidal nanoparticles where the gas molecules can find their way through the protective coating to the metal much more quickly.
In further series of tests, the scientists were able to validate the effectiveness of the new nanoparticles. To do so, they immersed steel plates both in electrolyte solutions with spheroidal zinc-phosphate nanoparticles and with flake-type zinc-phosphate nanoparticles in each case. After just half a day, the steel plates in the electrolytes with spheroidal nanoparticles were showing signs of corrosion whereas the steel plates in the electrolytes with flake-type nanoparticles were still in perfect condition and shining, even after three days. The researchers created their particles using standard, commercially available zinc salts, phosphoric acid and an organic acid as a complexing agent. The more complexing agent they added, the more anisotropic the nanoparticles became.
INM conducts research and development to create new materials — for today, tomorrow and beyond. Chemists, physicists, biologists, materials scientists and engineers team up to focus on these essential questions: Which material properties are new, how can they be investigated and how can they be tailored for industrial applications in the future?
Four research thrusts determine the current developments at INM:
- New materials for energy application,
- New concepts for medical surfaces,
- New surface materials for tribological systems and
- Nano safety and nano bio.
Research at INM is performed in three fields: Nanocomposite Technology, Interface Materials, and Bio Interfaces. INM — Leibniz Institute for New Materials, situated in Saarbrücken, is an internationally leading center for materials research. It is an institute of the Leibniz Association and has about 220 employees.
15 Apr 2016
Researchers have demonstrated that transparent ink containing gold, silver, and magnetic nanoparticles can be easily screen-printed onto various types of paper, with the nanoparticles being so small that they seep into the paper’s pores. Although invisible to the naked eye, the nanoparticles can be detected by the unique ways that they scatter light and by their magnetic properties. Since the combination of optical and magnetic signatures is extremely difficult to replicate, the nanoparticles have the potential to be an ideal anti-counterfeiting technology.
The researchers, Carlos Campos-Cuerva, Maciej Zieba, and coauthors at the University of Zaragoza in Zaragoza, Spain, and CIBER-BBN in Madrid, Spain, have published a paper on the anti-counterfeiting nanoparticle ink in a recent issue of Nanotechnology.
“We believe that it would be interesting to sell to different manufacturers their own personalized ink providing a specific combination of signals,” coauthor Manuel Arruebo at the University of Zaragoza and CIBER-BBN told Phys.org. “The nanoparticle-containing ink could then be used to mark a wide variety of supports including paper (documents, labels of wine, or drug packaging), plastic (bank or identity cards), textiles (luxury clothing or bags), and so on.”
Whereas previous methods of using nanoparticles as an anti-counterfeiting measure often require expensive, sophisticated equipment, the new technique is much simpler. The researchers attached the nanoparticles to the paper by standard screen-printing of transparent ink, and then authenticated the samples using commercially available optical and magnetic sensors.
A paper with the word “Nanotechnology,” where different pairs of letters are printed with different combinations of overlapping nanoparticle inks. Credit: Campos-Cuerva, et al. ©2016 IOP Publishing
“We demonstrated that the combination of nanomaterials providing different optical and magnetic properties on the same printed support is possible, and the resulting combined signals can be used to obtain a user-configurable label, providing a high degree of security in anti-counterfeiting applications using simple commercially available sensors at a low cost,” Arruebo said.
Although the nanoparticle ink is easy for the researchers to fabricate, attempting to replicate these authentication signals would be extremely difficult for a forger because the signals arise from the highly specific physical and chemical characteristics of the nanoparticles. Replicating the exact type, size, shape, and surface coating requires highly precise fabrication methods and an understanding of the correlation between the signals and these characteristics.
Making replication even more complicated is the fact that the combined optical and magnetic nanoparticles are printed on top of each other in the same spot, and this overlap creates an even more complex signal. Another advantage of the new technique is that the nanoparticles are able to withstand extreme temperatures and humidity under accelerated weathering conditions.
One of the greatest applications of the technology may be to prevent forgery of pharmaceutical drugs. Counterfeit medicine—which includes drugs that have incorrect or no active ingredients, as well as drugs that are intentionally mislabeled—is a growing problem throughout the world. The researchers plan to pursue such applications as well as further increase the security of the technology in future work.
“We plan to add more physical signals to the same tag by combining nanoparticles which could provide optical, magnetic, and electrical signals, etc., on the same printed spot,” Arruebo said.
More information: Carlos Campos-Cuerva, et al. “Screen-printed nanoparticles as anti-counterfeiting tags.” Nanotechnology. DOI: 10.1088/0957-4484/27/9/095702
Photo: M. Scott Brauer
National public-private consortium led by MIT will involve manufacturers, universities, agencies, companies.
A wide range of industries are expected to benefit from these revolutionary fibers and textiles, including apparel, consumer products, automotive, medical devices, and consumer electronics. “Fibers and fabrics are ubiquitous,” Fink says. “Our institute will go everywhere a fiber and fabric goes.”
An independent nonprofit founded by MIT has been selected to run a new, $317 million public-private partnership announced today by Secretary of Defense Ashton Carter.
The partnership, named the Advanced Functional Fibers of America (AFFOA) Institute, has won a national competition for federal funding to create the latest Manufacturing Innovation Institute. It is designed to accelerate innovation in high-tech, U.S.-based manufacturing involving fibers and textiles.
The proposal for the institute was led by Professor Yoel Fink, director of MIT’s Research Laboratory of Electronics (RLE). The partnership includes 32 universities, 16 industry members, 72 manufacturing entities, and 26 startup incubators, spread across 27 states and Puerto Rico.
This is the eighth Manufacturing Innovation Institute established to date, and the first to be headquartered in New England. The headquarters will be established in Cambridge, Massachusetts, in proximity to the MIT campus and its U.S. Army-funded Institute for Soldier Nanotechnology, as well as the Natick Soldier Research Development and Engineering Center.
This unique partnership, Fink says, has the potential to create a whole new industry, based on breakthroughs in fiber materials and manufacturing. These new fibers and the fabrics made from them will have the ability to see, hear, and sense their surroundings; communicate; store and convert energy; monitor health; control temperature; and change their color.
The new initiative will receive $75 million in federal funding out of a total of $317 million through cost sharing among the Department of Defense, industrial partners, venture capitalists, universities, nonprofits, and states including the Commonwealth of Massachusetts. The initial funding will cover a five-year period and will be administered through the new, independent, nonprofit organization set up for the purpose. The partnership, which will focus on both developing new technologies and training the workforce needed to operate and maintain these production systems, also includes a network of community colleges and experts in career and technical education for manufacturing.
“Massachusetts’s innovation ecosystem is reshaping the way that people interact with the world around them,” says Massachusetts Gov. Charlie Baker. “This manufacturing innovation institute will be the national leader in developing and commercializing textiles with extraordinary properties. It will extend to an exciting new field our ongoing efforts to nurture emerging industries, and grow them to scale in Massachusetts. And it will serve as a vital piece of innovation infrastructure, to support the development of the next generation of manufacturing technology, and the development of a highly skilled workforce.”
“Through this manufacturing innovation institute, Massachusetts researchers and Massachusetts employers will collaborate to unlock new advances in military technology, medical care, wearable technology, and fashion,” adds Massachusetts Lt. Gov. Karyn Polito. “This, in turn, will help drive business expansion, support the competitiveness of local manufacturers, and create new employment opportunities for residents across the Commonwealth.”
Announcing the new institute at an event at MIT, Carter stressed the importance of technology and innovation to the mission of the Department of Defense and to national security broadly: “The intersection of the two is truly an opportunity-rich environment. These issues matter. They have to do with our protection and our security, and creating a world where our fellow citizens can go to school and live their lives, and dream their dreams, and one day give their children a better future. Helping defend your country and making a better world is one of the noblest things that a business leader, a technologist, an entrepreneur, or a young person can do, and we’re all grateful to all of you for doing that with us.”
A new age of fabrics
For thousands of years, humans have used fabrics in much the same way, to provide basic warmth and aesthetics. Clothing represents “one of the most ancient forms of human expression,” Fink says, but one that is now, for the first time, poised to undergo a profound transformation — the dawn of a “fabric revolution.”
“What makes this point in time different? The answer is research,” Fink says: Objects that serve many complex functions are always made of multiple materials, whereas single-material objects, such as a drinking glass, usually have just a single, simple function. But now, new technology — some of it developed in Fink’s own laboratory — is changing all that, making it possible to integrate many materials and complex functional structures into a fabric’s very fibers, and to create fiber-based devices and functional fabric systems.
The semiconductor industry has shown how to combine millions of transistors into an integrated circuit that functions as a system; as described by “Moore’s law,” the number of devices and functions has doubled in computer chips every couple of years. Fink says the team envisions that the number of functions in a fiber will grow with similar speed, paving the way for highly functional fabrics.
The challenge now is to execute this vision, Fink says. While many textile and apparel companies and universities have figured out pieces of this puzzle, no single one has figured it all out.
“It turns out there is no company or university in the world that knows how to do all of this,” Fink says. “Instead of creating a single brick-and-mortar center, we set out to assemble and organize companies and universities that have manufacturing and ‘making’ capabilities into a network — a ‘distributed foundry’ capable of addressing the manufacturing challenges. To date, 72 manufacturing entities have signed up to be part of our network.”
“With a capable manufacturing network in place,” Fink adds, “the question becomes: How do we encourage and foster product innovation in this new area?” The answer, he says, lies at the core of AFFOA’s activities: Innovators across the country will be invited to execute “advanced fabric” products on prototyping and pilot scales. Moreover, the center will link these innovators with funding from large companies and venture capital investors, to execute their ideas through the manufacturing stage. The center will thus lower the barrier to innovation and unleash product creativity in this new domain, he says.
Promoting leadership in manufacturing
The federal selection process for the new institute was administered by the U.S. Department of Defense’s Manufacturing Technology Program and the U.S. Army’s Natick Soldier Research, Development and Engineering Center and Contracting Command in New Jersey. Retired Gen. Paul J. Kern will serve as chairman of the AFFOA Institute.
As explained in the original call for proposals to create this institute, the aim is to ensure “that America leads in the manufacturing of new products from leading edge innovations in fiber science, commercializing fibers and textiles with extraordinary properties. Known as technical textiles, these modern day fabrics and fibers boast novel properties ranging from being incredibly lightweight and flame resistant, to having exceptional strength. Technical textiles have wide-ranging applications, from advancing capabilities of protective gear allowing fire fighters to battle the hottest flames, to ensuring that a wounded soldier is effectively treated with an antimicrobial compression bandage and returned safely.”
In addition to Fink, the new partnership will include Tom Kochan, the George Maverick Bunker Professor of Management at MIT’s Sloan School of Management, who will serve as chief workforce officer coordinating the nationwide education and workforce development (EWD) plan. Pappalardo Professor of Mechanical Engineering Alexander Slocum will be the EWD deputy for education innovation. Other key MIT participants will include professors Krystyn Van Vliet from the Materials Science and Engineering and Biological Engineering departments; Peko Hosoi and Kripa Varanasi from the Department of Mechanical Engineering; and Gregory Rutledge from the Department of Chemical Engineering.
Among the industry partners who will be members of the partnership are companies such as Warwick Mills, DuPont, Steelcase, Nike, and Corning. Among the academic partners are Drexel University, the University of Massachusetts at Amherst, the University of Georgia, the University of Tennessee, and the University of Texas at Austin.
In a presentation last fall about the proposed partnership, MIT President L. Rafael Reif said, “We believe that partnerships — with industry and government and across academia — are critical to our capacity to create positive change.” He added, “Our nation has no shortage of smart, ambitious people with brilliant new ideas. But if we want a thriving economy, producing more and better jobs, we need more of those ideas to get to market faster.” Accelerating such implementation is at the heart of the new partnership’s goals.
Connecting skills, workers, and jobs
This partnership, Reif said, will be “a system that connects universities and colleges with motivated companies and with far-sighted government agencies, so we can learn from each other and work with each other. A system that connects workers with skills, and skilled workers with jobs. And a system that connects advanced technology ideas to the marketplace or to those who can get them to market.”
Part of the power of this new collaboration, Fink says, is combining the particular skills and resources of the different partners so that they “add up to something that’s more than the sum of the parts.” Existing large companies can contribute both funding and expertise, smaller startup companies can provide their creative new ideas, and the academic institutions can push the research boundaries to open up new technological possibilities.
“MIT recognizes that advancing manufacturing is vital to our innovation process, as we explored in our Production in the Innovation Economy (PIE) study,” says MIT Provost Martin Schmidt. “AFFOA will connect our campus even more closely with industries (large and small), with educational organizations that will develop the skilled workers, and with government at the state and federal level — all of whom are necessary to advance this new technology. AFFOA is an exciting example of the public-private partnerships that were envisioned in the recommendation of the Advanced Manufacturing Partnership.”
“Since MIT’s start, there has always been an emphasis on ‘mens et manus,’ using our minds and hands to make inventions useful at scales that impact the nation and the world,” adds Van Vliet, the director of manufacturing innovation for MIT’s Innovation Initiative, who has served as the faculty lead in coordinating MIT’s response to manufacturing initiatives that result from the Advanced Manufacturing Partnership. “What makes this new partnership very exciting is, this is for the first time a manufacturing institute headquartered in our region that connects our students and our faculty with local and national industrial partners, to really scale up production of many new fiber and textile technologies.”
“Participating in this group of visionaries from government, academia, and industry — who are all motivated by the goal of advancing a new model of American textile manufacturing and helping to develop new products for the public and defense sectors — has been an exciting process,” says Aleister Saunders, Drexel University’s senior vice provost for research and a leader of its functional fabrics center. “Seeing the success we’ve already had in recruiting partners at the local level leads me to believe that on a national level, these centers of innovation will be able to leverage intellectual capital and regional manufacturing expertise to drive forward new ideas and new applications that will revolutionize textile manufacturing across the nation.”
“Revolutionary fabrics and fibers are modernizing everything from battlefield communication to medical care,” says U.S. Congressmen Joe Kennedy III (D-Mass.). “That the Commonwealth would be chosen to lead the way is no surprise. From Lowell to Fall River, our ability to merge cutting-edge technology with age-old ingenuity has sparked a new day for the textile industry. With its unparalleled commitment to innovation, MIT is the perfect epicenter for scaling these efforts. I applaud President Reif, Professor Fink, and all of the partners involved for this tremendous success.”
The innovations that led to the “internet of things” and the widespread incorporation of digital technology into manufacturing have brought about a revolution whose potential is unlimited and will generate “brilliant ideas that people will be able to bring to this task of making sure that America stays number one in each and every one of these fields,” said Senator Ed Markey (D-Mass.) at the MIT event. “The new institute we are announcing today will help ensure that both Massachusetts and the United States can expand our technological edge in a new generation of fiber science.”
A wide range of industries are expected to benefit from these revolutionary fibers and textiles, including apparel, consumer products, automotive, medical devices, and consumer electronics. “Fibers and fabrics are ubiquitous,” Fink says. “Our institute will go everywhere a fiber and fabric goes.”
Genesis Nanotechnology, Inc. ~ “Great Things from Small Things”
13 Apr 2016
Combining quantum dots and organic molecules can enable solar cells to capture more of the sun’s light.
Light from the sun is our most abundant source of renewable energy, and learning how best to harvest this radiation is key for the world’s future power needs. Researchers at KAUST have discovered that the efficiency of solar cells can be boosted by combining inorganic semiconductor nanocrystals with organic molecules.
Quantum dots are nano-crystals that only measure roughly 10 nanometers across. An electron trapped by the dot has quite different properties from those of an electron free to move through a larger material.
“One of the greatest advantages of quantum dots for solar cell technologies is their optical properties’ tunability,” explained KAUST Assistant Professor of Chemical Science Omar Mohammed. “They can be controlled by varying the size of the quantum dot.”
Mohammed and his colleagues are developing lead sulfide quantum dots for optical energy harvesting; these tend to be larger than dots made from other materials. Accordingly, lead sulfide quantum dots can absorb light over a wider range of frequencies. This means they can absorb a greater proportion of the light from the sun when compared to other smaller dots.
To make a fully functioning solar cell, electrons must be able to move away from the quantum dot absorption region and flow toward an electrode. Ironically, the property of large lead sulfide quantum dots that makes them useful for broadband absorption—a smaller electron energy bandgap—also hinders this energy harvesting process. Previously, efficient electron transfer had only been achieved for lead sulfide quantum dots smaller than 4.3 nanometers across, which caused a cut-off in the frequency of light converted.
The innovation by Mohammed and the team was to mix lead sulfide quantum dots of various sizes with molecules from a family known as porphyrins. The researchers showed that by changing the porphyrin used, it is possible to control the charge transfer from large lead sulfide dots; while one molecule switched off charge transfer altogether, another one enabled transfer at a rate faster than 120 femtoseconds.
The team believe this improvement in energy harvesting ability is due to the interfacial electrostatic interactions between the negatively charged quantum dot surface and the positively charged porphyrin.
“With this approach, we can now extend the quantum dot size for efficient charge transfer to include most of the near-infrared spectral region, reaching beyond the previously reported cut-off,” stated Mohammed. “We hope next to implement this idea in solar-cells with different architectures to optimize efficiency.”
Explore further: Quantum dots with built-in charge boost solar cell efficiency by 50%
More information: Ala’a O. El-Ballouli et al. Overcoming the Cut-Off Charge Transfer Bandgaps at the PbS Quantum Dot Interface, Advanced Functional Materials (2015). DOI: 10.1002/adfm.201504035
A Chinese Perspective
Before the dawn of the new millennium, the then President of the USA Bill Clinton was invited by Science magazine to write an editorial. In the one-page piece, Science in the 21st century, he wrote: “Imagine a new century, full of promise, molded by science, shaped by technology, powered by knowledge. We are now embarking on our most daring explorations, unraveling the mysteries of our inner world and charting new routes to the conquest of disease” . In 2000, the US government firmly kicked off its significant and influential National Nanotechnology Initiative (NNI) program after integrating all resources from Federal agencies, including National Science Foundation, Department of Defense, Department of Energy, Department of Health and Human Services (NIH), National Institute of Standard Technology (NIST), National Aeronautics and Space Administration (NASA), Environmental Protection Agency (EPA), Homeland Security, United States Department of Agriculture (USDA), and Department of Justice.
The NNI established four goals:
(1) to advance a world-class nanotechnology research and development program;
(2) to foster the transfer of new technologies into products for commercial and public benefit;
(3) to develop and sustain educational resources, a skilled workforce, and supporting infrastructure and tools to advance nanotechnology; and
(4) to support responsible development of nanotechnology. The NNI significantly pushes nanotechnology research forward. In 2006, the prominence of nanotechnology research began to exceed medical research in terms of publication rate. That trend appears to be continuing as a result of the growth of products in commerce using nanotechnology and, for example, five-fold growth in number of countries with nanomaterials research centers.
The nanoscience and nanotechnology subject category of the Journal Citation Report (JCR) published by Thomson Reuters has increased rapidly. Correspondingly, both impact factors (published by Thomson Reuters) and SCImago Journal Rank values (SJR is published by Elsevier’s Scopus and powered by Google’s PageRank algorithms) of journals in the nanotechnology subject category have increased rapidly . The aggregate impact factor of nanoscience and nanotechnology has been rising at a breathtaking rate, compared with other subject categories, reaching the top 10 after 2011. The hype and hope of nanotechnology challenging many previously unimaginable goals are especially high now, and many believe in forthcoming breakthroughs in the areas of nanomaterial-based diagnostic imaging, complementation of diagnostic tools combined with therapeutic modalities (i.e., theranostics), or nanoencapsulation and nano-carriers of biotechnology products.
Today, it is estimated that total NNI funding, including the fiscal year 2014, is about $170 billion. Currently, there are more than 60 countriesthat have launched national nanotechnology programs . Governments and industry have invested millions of dollars in research funding in this rapidly growing field. By 2015, approximately one quarter trillion dollars will have been invested in nanotechnology by the American government and private sectors collectively. The continuous strategic investment in nanotechnology has made the United States a global leader in the field.
Ten years ago, when AAAS celebrated the 125th anniversary of the journalScience, it invited the President of Chinese Academy of Science (CAS) Chunli Bai to write an essay for the special section Global Voice of Science. The CAS President Chunli Bai’s essay, Ascent of Nanoscience in China  described the then development of nanotechnology and nanoscience in the country and openly announced the government’s ambition to compete with other countries in the field. In 2006, the Chinese government announced its Medium and Long-term Plan for the Development of Science and Technology (2006–2020), which identified nanotechnology as “a very promising area that could give China a chance of great-leap-forward development”. The plan introduced the new Chinese Science & Technology policy guidelines, which were later implemented by the Ministry of Science and Technology (MOST) that operates Nanoscience Research as a part of the State Key Science Research Plans. So far the Nanoscience Research program has invested about 1.0 billion RMB to support 28 nanotechnology projects. All of these endeavors led to the recent significantly rapid rise of nanotechnology in China as evidenced by its publications, industrial R&D and applications in the field.
The rapid development of nanotechnology-based science and technology in China attracted worldwide attention including from Demos, one of the UK’s most influential think tanks. Led by Wilsdon and Keeley, Demos completed an 18-month study, interviewing many leading scientists and policy makers of 71 Asian organizations, including two well-known Chinese nanotechnology academics Dr. Chen Wang (the then Director of National Center for Nanoscience and Technology) and Academician Zihe Rao (Director of CAS Institute of Biophysics).
After completion of the project, Wilsdon and Keeley published their findings in the book, China: The next science superpower?” . The authors wrote, “China in 2007 is the world’s largest technocracy: a country ruled by scientists and engineers who believe in the power of technology to deliver social and economic progress. Right now, the country is at an early stage in the most ambitious program of research investment since John F Kennedy embarked on the race to the moon. But statistics fail to capture the raw power of the changes that are under way, and the potential for Chinese science and innovation to head in new and surprising directions. Is China on track to become the world’s next science superpower?” Indeed, in recent years, China has emerged not only as a mass manufacturer, but also as one of the world’s leading nanotechnology nations. Many nanomaterial-based semiconductor products come from China and the country dominates in the nanotechnology area of most-cited academic articles: the top eighteen out of the twenty scholars are of Chinese origin .
Changes in nanotechnology-related geopolitical landscape
With strong governmental and private sector supports, nanotechnology and nanoscience R&D has developed rapidly in both the USA and China. As shown in Fig. 1A, from 2003 to 2013, the USA led in the area of global nanotechnology publications in terms of the numbers of papers and their quality determined by the number of citations and H-index. China followed USA in the field. For instance, the total nanotechnology publications from USA were 160,870 with total citations of 4056,278, whereas, China published 154,946 papers with total citations of 2049,072. The quality of an article is usually judged by the number of citations it receives, although other measures such as the number of downloads are becoming more accepted and used .
Based on the total number of publications and related citations, we have used weighted statistics to calculate the top countries actively involved in nanotechnology research (see original publication for full details). The statistics show that USA ranks number one, followed by China, Germany, Japan, Korea, France, UK, India, Italy, Spain, Taiwan (China), and others (Fig. 1A). EU countries are not too far behind in the field. Further analysis indicates that the number of nanotechnology-related publications increased from 23,957 in 2003 to 107,371 in 2013 world-wide (an increase of 4.48-folds). Among them, 3592 and 30.479 papers were contributed by China in 2003 and in 2013, respectively, that is an increase of 8.49 folds, which is about 2-fold higher than the global publication increase rate.
Bibliometric data of twenty leading nanotechnology journals shows that the USA is leading in nanotechnology research by far (see original publication for full details). The USA contributed 22,067 papers to the twenty journals from 2003 to 2013, whereas, China only published 3421 papers in these journals. If the analysis is limited to papers published in journals with an impact factor >20, the USA originated 1068 papers, followed by EU countries Germany (221), UK (193), France (149), and finally Japan (121). China only produced 76 papers with an impact factor >20, demonstrating that China has some significant hurdles to overcome to join the world’s top countries in nanotechnology development.
Interestingly, China is not lagging behind world leaders in all areas, for example, the gap between the USA and China is narrower in the field of nanomaterial research. Publications from China in Advanced Materials, Advanced Functional Materials, and Angew. Chem. Int. Edit. are not much less than those from the USA. In fact, China is leading in nanocomposites, chemical synthesis, and photocatalysis research (Fig. 1B and C). Chinese scientists published 1712 and 1580 papers in chemical synthesis and photocatalysis (from 2003 to 2013), respectively. The numbers exceed those from India, South Korea, Japan, USA, France, Germany, UK and Italy combined, suggesting that Chinese researchers have evolved their own research focuses and strengths over the years. On the other hand, this fact may also indicate an over-investment of resources in this area.
A list of the top ten universities and institutes world-wide (see original paper for full details), Top 10 Universities for Nanotechnology and Materials Science (U.S. has 5 in the Top 10) as well as those located within USA or China who contribute the most nanotechnology publications, reveals that the authorship of China’s nanotechnology publications is mostly concentrated in a small group of prestigious institutes and universities, reflecting the more centralized governance of China science, while authorship in the USA is more widely distributed. Indeed, the CAS possesses more resources than other competitors in China.
The geopolitical differences between the USA and China are also reflected in nanotechnology-related patent applications and industrialization. The numbers of nanotechnology-related patent applications to the US Patent and Trademark Office (USPTO), or the State Intellectual Property Office of China (SIPO) have increased from 405 in 2000 to 3729 in 2008 in USA, or from 105 in 2000 to 5030 in 2008 in China .
According to the China Patent Abstract Database managed by the SIPO, there were 30,863 nanotechnology patent applications from 1985 to 2009, and most of them were published after 2003. The central government has already built several state-level nanotechnology R&D incubators or bases, including the National Center for Nanoscience and Technology of China in Beijing, The State Engineering Research Center for Nanotechnology and Applications in Shanghai, National Institute of Nanotechnology and Engineering in Tianjin, Zhejiang–California International NanoSystems Institute, International Innovation Incubator of Nanotechnology, in Suzhou. In general, Beijing and Shanghai remain the two dominant nanotechnology centers, followed by Jiangsu and Zhejiang, reflecting the regional divergence of Chinese nanotechnology development .
The China–USA relationship is as compelling as it is complex. Approximately, one out of ten professionals in Silicon Valley’s high-tech workforce is from mainland China . In today’s global economy, the two great countries compete with each other in nanotechnology in a parallel and compatible manner. Historically, the United States has led the global high-tech and nanotechnology fields. However, the gap between USA and China in nanotechnology has narrowed significantly in recent years and American nanotechnology leadership faces challenges from all over the world.
With improved investment in research infrastructure and funding, China is sustaining the fastest economic growth in the world. Citizens’ participation in nanoscience and nanotechnology-related consensus conferences or stakeholder dialogues has become normal. This has not only had a significant impact on nanotechnology development in China, but also is democratically legitimate. Interest-based civil society interventions play an important role in the polycentric governance of nanoscience and nanotechnology to ensure that the related policies and regulations are made prudently after open argument and discussions . It would be interesting to watch, debate and decide which type of governmental system, the centralized one-party or the almost equally-divided two-party system, can more efficiently and effectively utilize public resources to produce nanotechnology products that better serve their own taxpayers, and the worldwide community as well.
*Fuzhou University and Rutgers University.
The authors are very grateful for supports fromChina MOST grant 2015CB931804 and NSFC grant 81273548 (LJ), 81571802 (YG), 21275002 (ZW); and US NIH grants (PJS)R01 AI117776 (NIAID/NIH), R37 AI051214 (NIAID/NIH), R01 CA155061 (NCI/NIH), andU54 AR055073 (NIAMS/NIH); the Graduate Student Fellowship Award from the American Association of Pharmaceutical Scientists Foundation (HYD).
This paper was originally published in Nano Today 11(1) (2016) 7–12, doi:10.1016/j.nantod.2016.02.001
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13 Apr 2016
Special from The World Economic Forum
Since the First Industrial Revolution, oil and gas have played a pivotal role in economic transformation and mobility. But now, with the prospects that major economies like the United States, China and European nations will try to shift away from oil, producers are coming to realize that their oil reserves under the ground – sometimes referred to as “black gold” – could become less valuable in the future than they are today.
Of the four scenarios for the future of the industry outlined in a new set of whitepapers from the Global Agenda on the Future of Oil and Gas, three of them envisage this type of world. Factors such as technological advancements, the falling price of batteries that power electric vehicles, and a post-COP21 push for cleaner energy could even drive oil use below 80 million barrels a day by 2040 – 15% lower than today.
We’re already feeling the effect
So what would a future of falling demand mean for the oil and gas industry?
Uncertainty about whether oil demand will continue to grow is already impacting the strategies of oil and gas firms. Through the 2000s and up until last year, the Organization of Petroleum Exporting Countries (OPEC), whose policies influence global oil supply and prices, took a revenues-oriented strategy, believing that scarce oil would be more valuable under the ground than out in the market, as global demand rose exponentially over time. Oil companies, too, responded to this world view by pursuing a business model that maximized adding as many reserves as possible to balance sheets and warehousing expensive assets.
Now, with new trends discussed in a new whitepaper, producers are coming to realize that oil under the ground might soon be less valuable than oil produced and sold in the coming years. This dramatic shift in expectations is changing the operating environment for the future of oil and gas.
A post-oil world: not all doom and gloom
Countries with large, low-cost reserves, such as Saudi Arabia, are rethinking strategies and will have to think twice about delaying production or development of reserves, in case they are unable to monetize those reserves over the long run. Saudi Arabia, for example, has recently announced that it is creating a $2 trillion mega-sovereign wealth fund, funded by sales of current petroleum industry assets, to prepare itself for an age when oil no longer dominates the global economy.
Declining revenues that could be reaped from exploitation of remaining oil reserves would adversely affect national revenues in many countries that have relied on oil as a major economic mainstay. Those countries will face pressing requirements for economic reform, with the risk of sovereign financial defaults rising.
But for the majority of the world’s population, structural transformations related to the future outlook for oil and gas offers an opportunity. If the global economy becomes less oil intensive, vulnerability to supply dislocations and price shocks that have plagued financial markets for decades will fade, with possible positive geopolitical implications. Moreover, many countries have reeled under the pressures of fuel subsidies to growing populations. According to the IMF, fuel subsidies cost $5.3 trillion in 2015 – around 6.5% of global GDP. Lower oil prices and larger range of alternative fuel choices would reverse this burden and lay the groundwork for shallower swings in prices for any one commodity.
Staying competitive in an industry under change
Eventually, players who remain competitive in the oil and gas industry will have to consider whether it can be more profitable to shareholders to develop profitable low-carbon sources of energy as supplement and ultimately replacements for oil and gas revenue sources, especially to maintain market share in the electricity sector.
This will require a change in the oil and gas industry investors’ mindset. To develop this flexible, supplemental leg to traditional oil and gas activities, the oil and gas industry may find new opportunities by addressing the technological challenges associated with the different parts of the renewable energy space, as well as how one can develop efficient combinations of large-scale energy storage and transportation solutions in a world with a lot of variable renewable electricity.
Industry players can benefit from partnerships for flex-fuel technologies to ease infrastructure transitions and improve their resiliency to carbon pricing by achieving carbon efficiency for end-use energy through collaborations with vehicle manufacturers and mobility firms. Such responses will enhance the industry’s attractiveness with customers and investors, and most importantly, will promote a smoother long-term energy transition.
The three whitepapers are available here.
A Rice University laboratory has found a way to turn common carbon fiber into graphene quantum dots, tiny specks of matter with properties expected to prove useful in electronic, optical and biomedical applications.
The Rice lab of materials scientist Pulickel Ajayan, in collaboration with colleagues in China, India, Japan and the Texas Medical Center, discovered a one-step chemical process that is markedly simpler than established techniques for making graphene quantum dots. The results were published online this month in the American Chemical Society’s journal Nano Letters.
“There have been several attempts to make graphene-based quantum dots with specific electronic and luminescent properties using chemical breakdown or e-beam lithography of graphene layers,” said Ajayan, Rice’s Benjamin M. and Mary Greenwood Anderson Professor of Mechanical Engineering and Materials Science and of Chemistry. “We thought that as these nanodomains of graphitized carbons already exist in carbon fibers, which are cheap and plenty, why not use them as the precursor?”
Quantum dots, discovered in the 1980s, are semiconductors that contain a size- and shape-dependent band gap. These have been promising structures for applications that range from computers, LEDs, solar cells and lasers to medical imaging devices. The sub-5 nanometer carbon-based quantum dots produced in bulk through the wet chemical process discovered at Rice are highly soluble, and their size can be controlled via the temperature at which they’re created.
The Rice researchers were attempting another experiment when they came across the technique. “We tried to selectively oxidize carbon fiber, and we found that was really hard,” said Wei Gao, a Rice graduate student who worked on the project with lead author Juan Peng, a visiting student from Nanjing University who studied in Ajayan’s lab last year. “We ended up with a solution and decided to look at a few drops with a transmission electron microscope.”
The specks they saw were bits of graphene or, more precisely, oxidized nanodomains of graphene extracted via chemical treatment of carbon fiber. “That was a complete surprise,” Gao said. “We call them quantum dots, but they’re two-dimensional, so what we really have here are graphene quantum discs.” Gao said other techniques are expensive and take weeks to make small batches of graphene quantum dots. “Our starting material is cheap, commercially available carbon fiber. In a one-step treatment, we get a large amount of quantum dots. I think that’s the biggest advantage of our work,” she said.
Further experimentation revealed interesting bits of information: The size of the dots, and thus their photoluminescent properties, could be controlled through processing at relatively low temperatures, from 80 to 120 degrees Celsius. “At 120, 100 and 80 degrees, we got blue, green and yellow luminescing dots,” she said.
They also found the dots’ edges tended to prefer the form known as zigzag. The edge of a sheet of graphene — the single-atom-thick form of carbon — determines its electrical characteristics, and zigzags are semiconducting.
Their luminescent properties give graphene quantum dots potential for imaging, protein analysis, cell tracking and other biomedical applications, Gao said. Tests at Houston’s MD Anderson Cancer Center and Baylor College of Medicine on two human breast cancer lines showed the dots easily found their way into the cells’ cytoplasm and did not interfere with their proliferation.
“The green quantum dots yielded a very good image,” said co-author Rebeca Romero Aburto, a graduate student in the Ajayan Lab who also studies at MD Anderson. “The advantage of graphene dots over fluorophores is that their fluorescence is more stable and they don’t photobleach. They don’t lose their fluorescence as easily. They have a depth limit, so they may be good for in vitro and in vivo (small animal) studies, but perhaps not optimal for deep tissues in humans.
“But everything has to start in the lab, and these could be an interesting approach to further explore for bioimaging,” Romero Alburto said. “In the future, these graphene quantum dotscould have high impact because they can be conjugated with other entities for sensing applications, too.”
Explore further: Single Atom Quantum Dots Bring Real Devices Closer (Video)
More information: Nano Lett., Article ASAP DOI: 10.1021/nl2038979
Ciphers and invisible ink – many of us experimented with these when we were children. A team of Chinese scientists has now developed a clever, high-tech version of “invisible ink”. As reported in the journal Angewandte Chemie, the ink is based on carbon nitride quantum dots. Information written with this ink is not visible under ambient or UV light; however, it can be seen with a fluorescence microplate reader. The writing can be further encrypted or decrypted by quenching or recovering the fluorescence with different reagents.
Fluorescing security inks are primarily used to ensure the authenticity of products or documents, such as certificates, stock certificates, transport documents, currency notes, or identity cards. Counterfeits may cost affected companies lost profits, and the poor quality of the false products may damage their reputations. In the case of sensitive products like pharmaceuticals and parts for airplanes and cars, human lives and health may be endangered. Counterfeiters have discovered how to imitate UV tags but it is significantly harder to copy security inks that are invisible under UV light.
Researchers working with Xinchen Wang and Liangqia Guo at Fuzhou University have now introduced an inexpensive “invisible” ink that increases the security of encoded data while also making it possible to encrypt and decrypt secure information.
The new ink is based on water-soluble quantum dots, nanoscopic “heaps” of a semiconducting material. Quantum dots have special optoelectronic properties that can be controlled by changing the size of the dots.
The scientists used quantum dots made from graphitic carbon nitride. This material consists of ring systems made of carbon and nitrogen atoms linked into two-dimensional molecular layers. The structure is similar to that of graphite (or graphene), one of the forms of pure carbon, but also has semiconductor properties.
Information written with this new ink is invisible under ambient and UV light because it is almost transparent in the visible light range and emits fluorescence with a peak in the UV range. The writing only becomes visible under a microplate reader like those used in biological fluorescence tests. In addition, the writing can be further encrypted and decrypted: treatment with oxalic acid renders it invisible to the microplate reader. Treatment with sodium bicarbonate reverses this process, making the writing visible to the reader once more.
Explore further: Luminescent ink from eggs
More information: Zhiping Song et al. Invisible Security Ink Based on Water-Soluble Graphitic Carbon Nitride Quantum Dots, Angewandte Chemie International Edition (2016). DOI: 10.1002/anie.201510945
Journal reference: Angewandte Chemie Angewandte Chemie International Edition
Provided by: Angewandte Chemie
31 Mar 2016
Recently, researchers at Tsinghua University, China have proposed a graphene-based nanostructured lithium metal anode for lithium metal batteries to inhibit dendrite growth and improve electrochemistry performance. They report their findings in Advanced Materials, published on March 16, 2016.
“Widely used lithium-ion batteries cannot satisfy the increasing requirement of energy storage systems in portable electronics and electric vehicles. New lithium metal anode batteries, like Li-S and Li-air batteries, are highly sought. Lithium metal provides an extremely high theoretical specific capacity, which is almost 10 times more energy than graphite,” said Prof. Qiang Zhang, at the Department of Chemical Engineering, Tsinghua University. “However, the practical applications of lithium metals are strongly hindered by lithium dendrite growth in continuous cycles. This induces safety concerns. The lithium dendrites may cause internal short circuits resulting in fire. Furthermore, the formation of lithium dendrites induces very low cycling efficiency.” The dendrite growth and unstable solid electrolyte interphase consume large amount of lithium and electrolyte, and therefore leading to irreversible battery capacity losses. Consequently, inhibiting the dendrites growth is highly expected.
Many approaches have been proposed to retard the growth of dendrites through electrolyte modification, artificial solid electrolyte interphase layers, electrode construction, and others. “We noticed that by decreasing the local current density heavily, lithium dendrite growth could be efficiently inhibited. Based on this concept, we employed unstacked graphene with an ultrahigh specific surface area to build a nanostructured anode. And it turned out to be a very efficient idea,” said Rui Zhang, a Ph.D. student and the first author. “Additionally, we have employed the dual-salt electrolyte to acquire more stable and more flexible solid electrolyte interphase, which can protect the lithium metal from further reactions with electrolyte.”
This graphene-based anode offered great improvement, including (1) ultralow local current density on the surface of graphene anode (a ten-thousandth of that on routine Cu foil-based anodes) induced by the large specific surface area of 1666 m2 g-1, which inhibited dendrite growth and brought uniform lithium deposition morphology; (2) high stable cycling capacity of 4.0 mAh mg-1 induced by the high pore volume (1.65 cm3 g-1) of unstacked graphene, over 10 times of the graphite anode in lithium-ion batteries (0.372 mAh mg-1); (3) high electrical conductivity (435 S cm-1), leading to low interface impedance, stable charging/discharging performance, and high cycling efficiencies.
“We hope that our research can point out a new strategy to deal with the dendrite challenge in lithium metal anodes. The ultralow local current density induced by conductive nanostructured anodes with high specific surface area can help improve the stability and electrochemistry performance of lithium metal anodes,” said Xin-Bing Cheng, a co-author of the work. Future investigation is required to design preferable anode structures and to produce more protective solid electrolyte interphase layers. The researchers also call for additional study of the diffusion behavior of Li ions and electrons in the process of lithium depositing and stripping to advance the commercial applications of lithium metal anodes.
Explore further: Nanostructure enlightening dendrite-free metal anode
More information: R. Zhang, X.-B. Cheng, C.-Z. Zhao, H.-J. Peng, J.-L. Shi, J.-Q. Huang, J. Wang, F. Wei, Q. Zhang. Conductive Nanostructured Scaffolds Render Low Local Current Density to Inhibit Lithium Dendrite Growth. Adv. Mater. 2016, 28, 2155-2162. DOI: 10.1002/adma.201504117.