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News Article | January 6, 2016
Site: phys.org

Their fortuitous pairing began shortly after the Chinese-born U.S. citizen and biochemical engineer arrived at NREL in 1992. She came as part of a newly created team tasked by what was then the Energy Department's National Bioethanol Program with exploring a new path for ethanol conversion for biofuels. At the time, global researchers were focusing on using yeast for alcohol production. "That [yeast] organism was the one people had studied for years. We at NREL decided to take a different approach," Zhang said. They chose instead the fermentative bacteria known to scientists as Zymomonas mobilis. "We felt it could be very promising," she said, explaining that the organism could consume glucose very fast—three times faster than yeast—as well as produce ethanol at high yield, which would potentially improve fuel production cost. By tapping that hunger, researchers could use the bacterium to speed up the process of turning the sugars (such as those derived from the long-chain cellulose and hemicellulose found in feedstock) into useable fuels and products. Next, the four-member NREL team successfully engineered the bug for pentose metabolism—pentoses are 5-carbon sugars that have been shown to be less appealing to organisms than 6-carbon sugars such as glucose. Zhang and the team had more positive results. "We ended up with a breakthrough," she said, and their work garnered national attention. In 1995, Science magazine published 'Metabolic Engineering of a Pentose Metabolism Pathway in Ethanologenic Zymomonas mobilis,' and the editors of R&D Magazine named the process a prestigious R&D 100 Award winner. Three cooperative research and development agreements (CRADAs) followed, including a major commitment with DuPont. The NREL/DuPont CRADA covered the entire span of biofuel technology, from biomass to ethanol. Scientists and engineers from DuPont and NREL worked collaboratively for years to further improve the biomass-to-ethanol conversion process, including the biocatalyst development using Zymomonas. Following some additional improvements, DuPont is now in the process of using the technology at their new cellulosic ethanol plant in Nevada, Iowa, where they plan to produce 30 million gallons of biofuels per year from the non-food parts of plants. "I'm pleased to see that kind of dream come true, and proud that the technology could end up in a commercial place," said Zhang, who traveled to the site for the October 30 grand opening of the $225 million plant. In honor of her many contributions, this year Zhang was given the Battelle Memorial Institute Inventor of the Year award as well as the Distinguished Innovator Award at NREL's Innovation and Technology Transfer Awards. At the tech transfer event, the Energy Department's Assistant Secretary for Energy Efficiency and Renewable Energy David Danielson presented her with the award, and she in turn thanked "my dear colleagues, the team that has a lot of talent and has put a lot of effort into this work." Zhang speaks after being named the winner of the Distinguished Innovator Award at NREL's 2015 Innovation and Technology Transfer Awards ceremony. Photo by Dennis Schroeder Her success is no surprise. Zhang, who grew up in a town outside of Shanghai in China, was always a good student. "I liked nature, and I'm good at math and science—but not quite as good in writing," she laughed. During that time, her country was undergoing major social change. When she was in high school in 1977, the government launched China's National College Entrance Examination—known as the gaokao ('big test' in Mandarin)— in an attempt to begin catching up to the rest of the world. She took the second national college entrance exam, a grueling three-day affair administered nationwide in July of 1978. About a month later, a plain letter informed her that she was admitted to East China University of Science and Engineering to study biochemical engineering. She was on her way, and did well in higher education. Following her graduation from East China University in 1982, she was encouraged to take a graduate school entrance exam, which she did—and received another acceptance letter to study at Osaka University in Japan. To prepare, her group underwent a six-month immersion in Japanese language studies. "It was hard, but there are some common characters in both languages, which helped," she said. Then they departed together on a new adventure. "It was my first trip on an airplane, and very exciting," she said, recalling joining about 150 students on a charter from Shanghai to Osaka. To cover basic expenses, she was given a Chinese National Scholarship from 1983 to 1989. Zhang supplemented that by teaching Chinese to Japanese nationals. "I'd get on a moped and drive to the city and teach class for an hour or two, and then come back to the lab to continue the experiments." After earning her Ph.D. in engineering, Zhang spent a year working for the Japanese firm Suntory, researching interferons. As she was looking ahead, political unrest spread in China. The protests and violence that rocked Tiananmen Square in the 'June Fourth Incident' in 1989 forced her to rethink her options. "I was concerned about going back to China, and I couldn't stay in Japan," she said, because her visa wasn't going to be renewed. However, one of her professors was hosting an American academic—who was impressed with her credentials, and invited her to the United States as a postdoctoral student. "I hadn't ever thought about the U.S., but it seemed like a good option," she said. Zhang had studied English, but admitted that her grasp was fairly basic. Following some wrangling for visas, she landed at the University of Michigan in February of 1990 as a research associate. Eventually, when it came time to look for a job, she searched the want ads in professional journals and discovered that an unfamiliar place called NREL was hiring. "I thought it was in North Carolina. Then I received a call from NREL," she laughed. "I didn't have a good grasp of U.S. geography." Still, she applied, interviewed—and was hired. Zhang is now looking at ways to create 'drop-in' biofuels—fuels that could be mixed in directly with jet fuel and other products. She is using Zymomonas to make a four-carbon molecule that is not only potentially a bulk chemical building block, but also can be further chemically converted to produce gasoline, diesel, and jet fuels. Photo by Dennis Schroeder She found a welcoming environment. Zhang has worked alongside a number of key NREL scientists including NREL Research Fellow Mike Himmel, a biochemist whose research on cellulase greatly simplified and lowered the cost of converting biomass to fuel. Her contributions at the lab, too, are notable. "Min has been a pioneer in the field, and has helped establish NREL as a leader since she arrived at NREL in 1992 as part of the Energy Department's then-new National Bioethanol Program," said Acting Biosciences Center Director Mark Davis. Although much of her time originally was spent doing foundational work with Zymomonas mobilis, Zhang hasn't stopped there, and has pushed the frontiers of biofuel research further. While observing a range of outcomes for various biofuels pretreatment processes, she focused on the problems of toxicity in breaking down cellulosic biomass for about four years beginning in 2008. "It had been a black box," she said, but reasoned that "unless we understand why the process is killing our organisms, it would be hard for us to improve [the process]. I decided to explore the black box. This was my mission." Zhang explained that "fermenting lignocellulosic sugars to ethanol is very challenging." In particular, "our organisms didn't like the toxicity—and they died," which prevented using some sugars for high-yield products. Just as she had done early on at NREL, she began systematically analyzing the problem. "I looked at the toxins, and why our [bugs] don't like them." Once she understood more and traced the origins of toxins—whether they were coming from biomass or from the pre-treatment process the engineers used to produce these soluble sugars—she was able to provide feedback to other researchers. Armed with new insight, NREL engineers were then able to make the processes more benign, and researchers were able to find improved organisms. "It gave engineers the context to improve," she said, and the hungry bug thrived in the sugar stream that is derived from the improved pretreatment process. She contributed in other ways to NREL's impact and reach. She has had opportunities to participate in the Energy Department's international program relating with China. As a lab representative on the Department's international bioenergy team, she has traveled to her homeland several times as part of a bilateral partnership in the Advanced Biofuels Forum. Her work has also evolved in the lab. In 2012, with cellulosic ethanol maturing, the Energy Department's Bioenergy Technologies Office was looking in fresh directions, including ways to create 'drop-in' biofuels—fuels that could be mixed in directly with jet fuel and other products. "I started exploring new pathways to produce molecules that can be upgraded to drop-in fuels," she said. Among her promising avenues are examinations with a fatty acid pathway using oleaginous yeast to make long-chain hydrocarbon molecules. Also, she is using Zymomonas to make a four-carbon molecule that is not only potentially a bulk chemical building block, but also can be further chemically converted to produce gasoline, diesel, and jet fuels. The team has made progress, she said: "We've seen exciting results." As she looks to the future, Zhang is proud of where she's been. And she's also pleased that she's been able to partner, so to speak, with various organisms. "Our bug is actually really happy now," she said of her current research and familiar teammate. And that's the way Zhang wants to keep it as she works toward new discoveries. Explore further: NREL teams with Navy, private industry to make jet fuel from switchgrass


News Article | December 15, 2015
Site: phys.org

Their fortuitous pairing began shortly after the Chinese-born U.S. citizen and biochemical engineer arrived at DOE's NREL in 1992. She came as part of a newly created team tasked by what was then the Energy Department's National Bioethanol Program with exploring a new path for ethanol conversion for biofuels. At the time, global researchers were focusing on using yeast for alcohol production. "That [yeast] organism was the one people had studied for years. We at NREL decided to take a different approach," Zhang said. They chose instead the fermentative bacteria known to scientists as Zymomonas mobilis. "We felt it could be very promising," she said, explaining that the organism could consume glucose very fast—three times faster than yeast—as well as produce ethanol at high yield, which would potentially improve fuel production cost. By tapping that hunger, researchers could use the bacterium to speed up the process of turning the sugars (such as those derived from the long-chain cellulose and hemicellulose found in feedstock) into useable fuels and products. Next, the four-member NREL team successfully engineered the bug for pentose metabolism—pentoses are 5-carbon sugars that have been shown to be less appealing to organisms than 6-carbon sugars such as glucose. Zhang and the team had more positive results. "We ended up with a breakthrough," she said, and their work garnered national attention. In 1995, Science magazine published "Metabolic Engineering of a Pentose Metabolism Pathway in Ethanologenic Zymomonas mobilis," and the editors of R&D Magazine named the process a prestigious R&D 100 Award winner. Three cooperative research and development agreements (CRADAs) followed, including a major commitment with DuPont. The NREL/DuPont CRADA covered the entire span of biofuel technology, from biomass to ethanol. Scientists and engineers from DuPont and NREL worked collaboratively for years to further improve the biomass-to-ethanol conversion process, including the biocatalyst development using Zymomonas. Following some additional improvements, DuPont is now in the process of using the technology at their new cellulosic ethanol plant in Nevada, Iowa, where they plan to produce 30 million gallons of biofuels per year from the non-food parts of plants. "I'm pleased to see that kind of dream come true, and proud that the technology could end up in a commercial place," said Zhang, who traveled to the site for the October 30 grand opening of the $225 million plant. In honor of her many contributions, this year Zhang was given the Battelle Memorial Institute Inventor of the Year award as well as the Distinguished Innovator Award at NREL's Innovation and Technology Transfer Awards. At the tech transfer event, DOE's Assistant Secretary for Energy Efficiency and Renewable Energy David Danielson presented her with the award, and she in turn thanked "my dear colleagues, the team that has a lot of talent and has put a lot of effort into this work." Her success is no surprise. Zhang, who grew up in a town outside of Shanghai in China, was always a good student. "I liked nature, and I'm good at math and science—but not quite as good in writing," she laughed. During that time, her country was undergoing major social change. When she was in high school in 1977, the government launched China's National College Entrance Examination—known as the gaokao ("big test" in Mandarin) in an attempt to begin catching up to the rest of the world. She took the second national college entrance exam—a grueling three-day affair administered nationwide in July of 1978. About a month later, a plain letter informed her that she was admitted to East China University of Science and Engineering to study biochemical engineering. She was on her way, and did well in higher education. Following her graduation from East China University in 1982, she was encouraged to take a graduate school entrance exam, which she did—and received another acceptance letter to study at Osaka University in Japan. To prepare, her group underwent a six-month immersion in Japanese language studies. "It was hard, but there are some common characters in both languages, which helped," she said. Then they departed together on a new adventure. "It was my first trip on an airplane, and very exciting," she said, recalling joining about 150 students on a charter from Shanghai to Osaka. To cover basic expenses, she was given a Chinese National Scholarship from 1983 to 1989. Zhang supplemented that by teaching Chinese to Japanese nationals. "I'd get on a moped and drive to the city and teach class for an hour or two, and then come back to the lab to continue the experiments." After earning her Ph.D. in engineering, Zhang spent a year working for the Japanese firm Suntory, researching interferons. As she was looking ahead, political unrest spread in China. The protests and violence that rocked Tiananmen Square in the "June Fourth Incident" in 1989 forced her to rethink her options. "I was concerned about going back to China, and I couldn't stay in Japan," she said, because her visa wasn't going to be renewed. However, one of her professors was hosting an American academic—who was impressed with her credentials, and invited her to the United States as a postdoctoral student. "I hadn't ever thought about the U.S., but it seemed like a good option," she said. Zhang had studied English, but admitted that her grasp was fairly basic. Following some wrangling for visas, she landed at the University of Michigan in February of 1990 as a research associate. Eventually, when it came time to look for a job, she searched the want ads in professional journals and discovered that an unfamiliar place called NREL was hiring. "I thought it was in North Carolina. Then I received a call from NREL," she laughed. "I didn't have a good grasp of U.S. geography." Still, she applied, interviewed—and was hired. She found a welcoming environment. Zhang has worked alongside a number of key NREL scientists including NREL Research Fellow Mike Himmel, a biochemist whose research on cellulase greatly simplified and lowered the cost of converting biomass to fuel. Her contributions at the lab, too, are notable. "Min has been a pioneer in the field, and has helped establish NREL as a leader since she arrived at NREL in 1992 as part of the Energy Department's then-new National Bioethanol Program," said Acting Biosciences Center Director Mark Davis. Although much of her time originally was spent doing foundational work with Zymomonas mobilis, Zhang hasn't stopped there, and has pushed the frontiers of biofuel research further. While observing a range of outcomes for various biofuels pretreatment processes, she focused on the problems of toxicity in breaking down cellulosic biomass for about four years beginning in 2008. "It had been a black box," she said, but reasoned that "unless we understand why the process is killing our organisms, it would be hard for us to improve [the process]. I decided to explore the black box. This was my mission." Zhang explained that "fermenting lignocellulosic sugars to ethanol is very challenging." In particular, "our organisms didn't like the toxicity—and they died," which prevented using some sugars for high-yield products. Just as she had done early on at NREL, she began systematically analyzing the problem. "I looked at the toxins, and why our [bugs] don't like them." Once she understood more and traced the origins of toxins—whether they were coming from biomass or from the pre-treatment process the engineers used to produce these soluble sugars—she was able to provide feedback to other researchers. Armed with new insight, NREL engineers were then able to make the processes more benign, and researchers were able to find improved organisms. "It gave engineers the context to improve," she said, and the hungry bug thrived in the sugar stream that is derived from the improved pretreatment process. She contributed in other ways to NREL's impact and reach. She has had opportunities to participate in the Energy Department's international program relating with China. As a lab representative on the Department's international bioenergy team, she has traveled to her homeland several times as part of a bilateral partnership in the Advanced Biofuels Forum. Her work has also evolved in the lab. In 2012, with cellusloic ethanol maturing, the Energy Department's Bioenergy Technologies Office was looking in fresh directions, including ways to create "drop-in" biofuels—fuels that could be mixed in directly with jet fuel and other products. "I started exploring new pathways to produce molecules that can be upgraded to drop-in fuels," she said. Among her promising avenues are examinations with a fatty acid pathway using oleaginous yeast to make long-chain hydrocarbon molecules. Also, she is using Zymomonas to make a four-carbon molecule that is not only potentially a bulk chemical building block, but also can be further chemically converted to produce gasoline, diesel, and jet fuels. The team has made progress, she said: "We've seen exciting results." As she looks to the future, Zhang is proud of where she's been. And she's also pleased that she's been able to partner, so to speak, with various organisms. "Our bug is actually really happy now," she said of her current research and familiar teammate. And that's the way Min wants to keep it as she works toward new discoveries. Explore further: NREL teams with Navy, private industry to make jet fuel from switchgrass


The team has designed the most efficient catalyst for storing energy in chemical form, by splitting water into hydrogen and oxygen, just like plants do during photosynthesis. Oxygen is released harmlessly into the atmosphere, and hydrogen, as H2, can be converted back into energy using hydrogen fuel cells. "Today on a solar farm or a wind farm, storage is typically provided with batteries. But batteries are expensive, and can typically only store a fixed amount of energy," says Sargent. "That's why discovering a more efficient and highly scalable means of storing energy generated by renewables is one of the grand challenges in this field." You may have seen the popular high-school science demonstration where the teacher splits water into its component elements, hydrogen and oxygen, by running electricity through it. Today this requires so much electrical input that it's impractical to store energy this way—too great proportion of the energy generated is lost in the process of storing it. This new catalyst facilitates the oxygen-evolution portion of the chemical reaction, making the conversion from H2O into O2 and H2 more energy-efficient than ever before. The intrinsic efficiency of the new catalyst material is over three times more efficient than the best state-of-the-art catalyst. The new catalyst is made of abundant and low-cost metals tungsten, iron and cobalt, which are much less expensive than state-of-the-art catalysts based on precious metals. It showed no signs of degradation over more than 500 hours of continuous activity, unlike other efficient but short-lived catalysts. Their work was published today in the leading journal Science. "With the aid of theoretical predictions, we became convinced that including tungsten could lead to a better oxygen-evolving catalyst. Unfortunately, prior work did not show how to mix tungsten homogeneously with the active metals such as iron and cobalt," says Dr. Bo Zhang, one of the study's lead authors. "We invented a new way to distribute the catalyst homogenously in a gel, and as a result built a device that works incredibly efficiently and robustly." This research united engineers, chemists, materials scientists, mathematicians, physicists, and computer scientists across three countries. A chief partner in this joint theoretical-experimental study was a leading team of theorists at Stanford University and SLAC National Accelerator Laboratory under the leadership of Dr. Aleksandra Vojvodic. The international collaboration included researchers at East China University of Science & Technology, Tianjin University, Brookhaven National Laboratory, Canadian Light Source and the Beijing Synchrotron Radiation Facility. "The team developed a new materials synthesis strategy to mix multiple metals homogeneously—thereby overcoming the propensity of multi-metal mixtures to separate into distinct phases," said Jeffrey C. Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems at Massachusetts Institute of Technology. "This work impressively highlights the power of tightly coupled computational materials science with advanced experimental techniques, and sets a high bar for such a combined approach. It opens new avenues to speed progress in efficient materials for energy conversion and storage." "This work demonstrates the utility of using theory to guide the development of improved water-oxidation catalysts for further advances in the field of solar fuels," said Gary Brudvig, a professor in the Department of Chemistry at Yale University and director of the Yale Energy Sciences Institute. "The intensive research by the Sargent group in the University of Toronto led to the discovery of oxy-hydroxide materials that exhibit electrochemically induced oxygen evolution at the lowest overpotential and show no degradation," said University Professor Gabor A. Somorjai of the University of California, Berkeley, a leader in this field. "The authors should be complimented on the combined experimental and theoretical studies that led to this very important finding."


News Article | March 29, 2016
Site: www.cemag.us

We can’t control when the wind blows and when the sun shines, so finding efficient ways to store energy from alternative sources remains an urgent research problem. Now, a group of researchers led by Professor Ted Sargent at the University of Toronto’s Faculty of Applied Science & Engineering may have a solution inspired by nature. The team has designed the most efficient catalyst for storing energy in chemical form, by splitting water into hydrogen and oxygen, just like plants do during photosynthesis. Oxygen is released harmlessly into the atmosphere, and hydrogen, as H , can be converted back into energy using hydrogen fuel cells. “Today on a solar farm or a wind farm, storage is typically provided with batteries. But batteries are expensive, and can typically only store a fixed amount of energy,” says Sargent. “That’s why discovering a more efficient and highly scalable means of storing energy generated by renewables is one of the grand challenges in this field.” You may have seen the popular high-school science demonstration where the teacher splits water into its component elements, hydrogen and oxygen, by running electricity through it. Today this requires so much electrical input that it’s impractical to store energy this way — too great proportion of the energy generated is lost in the process of storing it. This new catalyst facilitates the oxygen-evolution portion of the chemical reaction, making the conversion from H O into O and H more energy-efficient than ever before. The intrinsic efficiency of the new catalyst material is over three times more efficient than the best state-of-the-art catalyst. The new catalyst is made of abundant and low-cost metals tungsten, iron and cobalt, which are much less expensive than state-of-the-art catalysts based on precious metals. It showed no signs of degradation over more than 500 hours of continuous activity, unlike other efficient but short-lived catalysts. Their work was published this week in the leading journal Science. “With the aid of theoretical predictions, we became convinced that including tungsten could lead to a better oxygen-evolving catalyst. Unfortunately, prior work did not show how to mix tungsten homogeneously with the active metals such as iron and cobalt,” says Dr. Bo Zhang, one of the study’s lead authors. “We invented a new way to distribute the catalyst homogenously in a gel, and as a result built a device that works incredibly efficiently and robustly.” This research united engineers, chemists, materials scientists, mathematicians, physicists, and computer scientists across three countries. A chief partner in this joint theoretical-experimental studies was a leading team of theorists at Stanford University and SLAC National Accelerator Laboratory under the leadership of Dr. Aleksandra Vojvodic. The international collaboration included researchers at East China University of Science & Technology, Tianjin University, Brookhaven National Laboratory, Canadian Light Source, and the Beijing Synchrotron Radiation Facility. “The team developed a new materials synthesis strategy to mix multiple metals homogeneously — thereby overcoming the propensity of multi-metal mixtures to separate into distinct phases,” says Jeffrey C. Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems at Massachusetts Institute of Technology. “This work impressively highlights the power of tightly coupled computational materials science with advanced experimental techniques, and sets a high bar for such a combined approach. It opens new avenues to speed progress in efficient materials for energy conversion and storage.” “This work demonstrates the utility of using theory to guide the development of improved water-oxidation catalysts for further advances in the field of solar fuels,” says Gary Brudvig, a professor in the Department of Chemistry at Yale University and director of the Yale Energy Sciences Institute. “The intensive research by the Sargent group in the University of Toronto led to the discovery of oxy-hydroxide materials that exhibit electrochemically induced oxygen evolution at the lowest overpotential and show no degradation,” says University Professor Gabor A. Somorjai of the University of California, Berkeley, a leader in this field. “The authors should be complimented on the combined experimental and theoretical studies that led to this very important finding.” Sargent is the Canada Research Chair in Nanotechnology. The group’s work was supported in large part by the Ontario Research Fund-Research Excellence Program, NSERC, the CIFAR Bio-Inspired Solar Energy Program, and the U.S. Department of Energy. Source: University of Toronto


Home > Press > Saving sunshine for a rainy day: New catalyst offers efficient storage of green energy: Team led by U of T Engineering designs world's most efficient catalyst for storing energy as hydrogen by splitting water molecules Abstract: We can't control when the wind blows and when the sun shines, so finding efficient ways to store energy from alternative sources remains an urgent research problem. Now, a group of researchers led by Professor Ted Sargent at the University of Toronto's Faculty of Applied Science & Engineering may have a solution inspired by nature. The team has designed the most efficient catalyst for storing energy in chemical form, by splitting water into hydrogen and oxygen, just like plants do during photosynthesis. Oxygen is released harmlessly into the atmosphere, and hydrogen, as H2, can be converted back into energy using hydrogen fuel cells. "Today on a solar farm or a wind farm, storage is typically provided with batteries. But batteries are expensive, and can typically only store a fixed amount of energy," says Sargent. "That's why discovering a more efficient and highly scalable means of storing energy generated by renewables is one of the grand challenges in this field." You may have seen the popular high-school science demonstration where the teacher splits water into its component elements, hydrogen and oxygen, by running electricity through it. Today this requires so much electrical input that it's impractical to store energy this way -- too great proportion of the energy generated is lost in the process of storing it. This new catalyst facilitates the oxygen-evolution portion of the chemical reaction, making the conversion from H2O into O2 and H2 more energy-efficient than ever before. The intrinsic efficiency of the new catalyst material is over three times more efficient than the best state-of-the-art catalyst. The new catalyst is made of abundant and low-cost metals tungsten, iron and cobalt, which are much less expensive than state-of-the-art catalysts based on precious metals. It showed no signs of degradation over more than 500 hours of continuous activity, unlike other efficient but short-lived catalysts. Their work was published today in the leading journal Science. "With the aid of theoretical predictions, we became convinced that including tungsten could lead to a better oxygen-evolving catalyst. Unfortunately, prior work did not show how to mix tungsten homogeneously with the active metals such as iron and cobalt," says Dr. Bo Zhang, one of the study's lead authors. "We invented a new way to distribute the catalyst homogenously in a gel, and as a result built a device that works incredibly efficiently and robustly." This research united engineers, chemists, materials scientists, mathematicians, physicists, and computer scientists across three countries. A chief partner in this joint theoretical-experimental study was a leading team of theorists at Stanford University and SLAC National Accelerator Laboratory under the leadership of Dr. Aleksandra Vojvodic. The international collaboration included researchers at East China University of Science & Technology, Tianjin University, Brookhaven National Laboratory, Canadian Light Source and the Beijing Synchrotron Radiation Facility. "The team developed a new materials synthesis strategy to mix multiple metals homogeneously -- thereby overcoming the propensity of multi-metal mixtures to separate into distinct phases," said Jeffrey C. Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems at Massachusetts Institute of Technology. "This work impressively highlights the power of tightly coupled computational materials science with advanced experimental techniques, and sets a high bar for such a combined approach. It opens new avenues to speed progress in efficient materials for energy conversion and storage." "This work demonstrates the utility of using theory to guide the development of improved water-oxidation catalysts for further advances in the field of solar fuels," said Gary Brudvig, a professor in the Department of Chemistry at Yale University and director of the Yale Energy Sciences Institute. "The intensive research by the Sargent group in the University of Toronto led to the discovery of oxy-hydroxide materials that exhibit electrochemically induced oxygen evolution at the lowest overpotential and show no degradation," said University Professor Gabor A. Somorjai of the University of California, Berkeley, a leader in this field. "The authors should be complimented on the combined experimental and theoretical studies that led to this very important finding." ### Professor Sargent is the Canada Research Chair in Nanotechnology. The group's work was supported in large part by the Ontario Research Fund--Research Excellence Program, NSERC, the CIFAR Bio-Inspired Solar Energy Program and the U.S. Department of Energy. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | March 29, 2016
Site: www.rdmag.com

With a combination of theory and clever, meticulous gel-making, scientists from the Department of Energy’s SLAC National Accelerator Laboratory and the University of Toronto have developed a new type of catalyst that’s three times better than the previous record-holder at splitting water into hydrogen and oxygen—the vital first step in making fuels from renewable solar and wind power. The research, published in the journal Science, outlines a potential way to make a future generation of water-splitting catalysts from three abundant metals—iron, cobalt and tungsten—rather than the rare, costly metals that many of today’s catalysts rely on. “The good things about this catalyst are that it’s easy to make, its production can be very easily scaled up without any super-advanced tools, it’s consistent and it’s very robust,” said Aleksandra Vojvodic, a SLAC staff scientist with the SUNCAT Center for Interface Science and Catalysis who led the theoretical side of the work. Scientists have been searching for an efficient way to store electricity generated by solar and wind power so it can be used any time—not just when the sun shines and breezes blow. One way to do that is to use the electrical current to split water molecules into hydrogen and oxygen, and store the hydrogen to use later as fuel. This reaction takes place in several steps, each requiring a catalyst—a substance that promotes chemical reactions without being consumed itself—to move it briskly along. In this case, the scientists focused on a step where oxygen atoms pair up to form a gas that bubbles away, which has been a bottleneck in the process. In previous work, Vojvodic and her SUNCAT colleagues had used theory and computation to look at water-splitting oxide catalysts that contain one or two metals and predict ways to make them more active. For this study, Edward H. Sargent, a professor of electrical and computer engineering at the University of Toronto, asked them to look at the effect of adding tungsten—a heavy, dense metal used in light bulb filaments and radiation shielding—to an iron-cobalt catalyst that worked, but not very efficiently. With the aid of powerful computers at SLAC and elsewhere and state-of-the-art computational tools, the SUNCAT team determined that adding tungsten should dramatically increase the catalyst’s activity—especially if the three metals could be mixed so thoroughly that their atoms were uniformly distributed near the active site of the catalyst, where the reaction takes place, rather than separating into individual clusters as they normally tend to do. “Tungsten is quite a large atom compared to the other two, and when you add a little bit of it, it expands the atomic lattice, and this affects the reaction not only geometrically but also electronically,” Vojvodic said. “We were able to understand, on the atomic scale, why it works, and then that was verified experimentally.” Based on that information, Sargent’s team developed a novel way to distribute the three metals uniformly within the catalyst: They dissolved the metals and other ingredients in a solution and then slowly turned the solution into a gel at room temperature, tweaking the process so the metal atoms did not clump together. The gel was then dried into a white powder whose particles were riddled with tiny pores, increasing the surface area where chemicals can attach and react with each other. In tests, the catalyst was able to generate oxygen gas three times faster, per unit weight, than the previous record-holder, Sargent said, and it also proved to be stable through hundreds of reaction cycles. “It’s a big advance, although there’s still more room to improve,” he said. “And we will need to make catalysts and electrolysis systems even more efficient, cost effective and high intensity in their operation in order to drive down the cost of producing renewable hydrogen fuels to an even more competitive level.” Sargent said the researchers hope to use the same method to develop other three-metal catalysts for splitting water and also for splitting carbon dioxide, a greenhouse gas released by burning fossil fuels, to make renewable fuels and chemical feed stocks. He and five other members of the University of Toronto team have filed for a provisional patent on the technique for preparing the catalyst. “There are a lot of things we further need to understand,” Vojvodic said. “Are there other abundant metals we can test as mixtures in oxides? What are the optimal mixtures of the components? How stable is the catalyst, and how can we scale up its production? It needs to be tested at the device level, really.” Jeffrey C. Grossman, a professor of materials science and engineering at MIT who was not involved in the study, said, “The work impressively highlights the power of tightly coupled computational materials science with advanced experimental techniques, and sets a high bar for such a combined approach. It opens new avenues to speed progress in efficient materials for energy conversion and storage." SLAC research associate Michal Bajdich and Stanford postdoctoral researcher Max García-Melchor also contributed to this work, along with researchers from the DOE’s Brookhaven National Laboratory; East China University of Science & Technology, Tianjin University and the Beijing Synchrotron Radiation Facility in China; and the Canadian Light Source. The research was funded by a number of sources, including the Ontario Research Fund–Research Excellence Program, Natural Sciences and Engineering Research Council of Canada and the CIFAR Bio-Inspired Solar Energy Program, as well as the DOE Office of Science, which funds SUNCAT, and the SLAC Laboratory Directed Research and Development program.


« ABI Research: 6 transformative paradigms driving toward smart, sustainable automotive transportation | Main | First minimal synthetic bacterial cell designed and constructed by scientists at Venter Institute and Synthetic Genomics; 473 genes » Scientists from the Department of Energy’s SLAC National Accelerator Laboratory and the University of Toronto have developed a new type of ternary catalyst for the oxygen evolution reaction (OER) in water-splitting that exhibits a turnover frequency (TOF) that’s more than three-times above the TOF and mass activities of optimized control catalysts and the state-of-art NiFeOOH catalyst. The research, published in the journal Science, outlines a potential way to make a future generation of water-splitting catalysts from three abundant metals—iron (Fe), cobalt (Co) and tungsten (W)—rather than the rare, costly metals on which many of today’s catalysts rely. The gelled FeCoW oxy-hydroxide material exhibits the lowest overpotential (191 mV) reported at 10 mA per square centimeter in alkaline electrolyte. Further, the ternary catalyst showed no evidence of degradation following more than 500 hours of operation. The good things about this catalyst are that it’s easy to make, its production can be very easily scaled up without any super-advanced tools, it’s consistent, and it’s very robust. —Aleksandra Vojvodic, a SLAC staff scientist with the SUNCAT Center for Interface Science and Catalysis who led the theoretical side of the work In previous work, Vojvodic and her SUNCAT colleagues had used theory and computation to look at water-splitting oxide catalysts that contain one or two metals and predict ways to make them more active. For this study, Edward H. Sargent, a professor of electrical and computer engineering at the University of Toronto, asked them to look at the effect of adding tungsten to an iron-cobalt catalyst that worked, but not very efficiently. With the aid of powerful computers at SLAC and elsewhere and state-of-the-art computational tools, the SUNCAT team determined that adding tungsten should significantly increase the catalyst’s activity—especially if the three metals could be mixed so thoroughly that their atoms were uniformly distributed near the active site of the catalyst, where the reaction takes place, rather than separating into individual clusters as they normally tend to do. Based on that information, Sargent’s team developed a novel way to distribute the three metals uniformly within the catalyst: They dissolved the metals and other ingredients in a solution and then slowly turned the solution into a gel at room temperature, tweaking the process so the metal atoms did not clump together. The gel was then dried into a white powder whose particles were riddled with tiny pores, increasing the surface area where chemicals can attach and react with each other. In tests, the catalyst was able to generate oxygen gas three times faster, per unit weight, than the previous record-holder, Sargent said, and it also proved to be stable through hundreds of reaction cycles. Sargent said the researchers hope to use the same method to develop other three-metal catalysts for splitting water and also for splitting carbon dioxide, a greenhouse gas released by burning fossil fuels, to make renewable fuels and chemical feed stocks. He and five other members of the University of Toronto team have filed for a provisional patent on the technique for preparing the catalyst. There are a lot of things we further need to understand. Are there other abundant metals we can test as mixtures in oxides? What are the optimal mixtures of the components? How stable is the catalyst, and how can we scale up its production? It needs to be tested at the device level, really. Jeffrey C. Grossman, a professor of materials science and engineering at MIT who was not involved in the study, said: SLAC research associate Michal Bajdich and Stanford postdoctoral researcher Max García-Melchor also contributed to this work, along with researchers from the DOE’s Brookhaven National Laboratory; East China University of Science & Technology, Tianjin University and the Beijing Synchrotron Radiation Facility in China; and the Canadian Light Source. The research was funded by a number of sources, including the Ontario Research Fund – Research Excellence Program, Natural Sciences and Engineering Research Council of Canada and the CIFAR Bio-Inspired Solar Energy Program, as well as the DOE Office of Science, which funds SUNCAT, and the SLAC Laboratory Directed Research and Development program.


Yang J.-W.,East China University of Science | Dong X.-J.,Shanghai Institute of Pharmaceutical Industry | Li Z.-L.,Shanghai Institute of Pharmaceutical Industry | Guan C.-C.,East China University of Science | And 4 more authors.
Huadong Ligong Daxue Xuebao/Journal of East China University of Science and Technology | Year: 2013

The in vitro antimicrobial efficacy of α- or β-O-galactolipids and their anomeric mixtures with saturated carbon chains of different length was assessed by Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Results reveal that the anomeric mixture of two O-galactolipids with a 12C-lipid end inhibit Bacillus subtilis at a low concentration. The minimal inhibitory concentration of this mixture is determined to be 0.06 mmol/L.


News Article | January 29, 2016
Site: cen.acs.org

Carbon nanotubes are exceptionally strong and stretchy. To take advantage of these properties, scientists have been trying to make thin sheets from nanotubes that could be used as structural coatings for vehicle or aerospace parts or for protective military and sports gear. But nanotube films’ mechanical properties have so far come nowhere close to those of individual nanotubes. Researchers now report a simple fabrication method to make carbon nanotube films that are five times as strong as those made before—and stronger than films made from Kevlar or carbon fiber (Nano Lett. 2016, DOI: 10.1021/acs.nanolett.5b03863). The new films have densely packed nanotubes, nearly all oriented parallel to each other, which give the films their superior strength, says Jian Nong Wang, a professor of mechanical and power engineering at East China University of Science & Technology. Many groups have tried to align and assemble nanotubes into films, typically by spraying or filtering suspensions of nanotubes onto a surface. But these techniques use short nanotubes and do not align the tubes well, so the films are weak. Wang and his colleagues made nanotubes with a process akin to glass blowing: Using a stream of nitrogen gas, they injected ethanol, with a small amount of ferrocene and thiophene added as catalysts, into a 50-mm-wide horizontal tube placed in furnace at 1,150–1,130 °C. A hollow cylinder with walls made of aligned carbon nanotubes forms in the furnace and emerges from the other end of the tube, driven by the nitrogen. As the tube emerges, the researchers wind the floating carbon nanotube cylinder onto a rotating drum. As the drum spins, the hollow cylinder condenses and flattens into a two-layered, black, carbon nanotube film. Faster winding resulted in better nanotube alignment, the researchers found. Finally, they packed the nanotubes even more densely by pressing the film repeatedly between two rollers. The resulting films had an average strength of 9.6 gigapascals. By comparison, the strength of nanotube films made so far has been around 2 GPa, while that for Kevlar fibers and commercially used carbon fibers is around 3.7 and 7 GPa, respectively. The films are four times as pliable as conventional carbon fibers, and can elongate by 8% on average as opposed to 2% for carbon fibers. Wang says that in addition to their useful mechanical properties, the films have high electrical conductivity, which could make them useful as electrodes for wearable devices and as artificial muscles. Yutaka Matsuo, a professor of chemistry at the University of Tokyo, says that the simplicity of this mechanical winding technique to align nanotubes and make ultra-strong films is notable. The technique also results in pure carbon films, whereas earlier, solution-based methods that press premade nanotubes into films require surfactants that contaminate the films.

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