By some estimates, the amount of solar energy that reaches the earth’s surface in a year is greater than the amount of all the energy that we can produce using non-renewable resources. The technology needed to convert sunlight into electricity has developed rapidly, but efficiency in storage and distribution of power remains an important issue, making solar energy impractical on a large scale.
However, breakthroughs by researchers at UVA College and Graduate School of Arts & Sciences, California Institute of Technology and the U.S. Department of National Argonne, Lawrence Berkeley National Laboratory and Brookhaven National Laboratory can remove significant barriers from the process, a discovery that represents a giant step forward. energy-clean front.
One way to take advantage of solar energy is to use solar electricity to split water molecules into oxygen and hydrogen. The hydrogen produced by the process is stored as fuel, in a form that can be transferred from one place to another and is used to generate power on demand. To divide water molecules into components, they must be catalysts, but the catalytic materials currently used in the process, also known as oxygen evolution reactions, are not efficient enough to make the process practical.
Using innovative chemical strategies developed at UVA, however, a team of researchers led by chemical professors Sen Zhang and T. Brent Gunnoe has developed new catalyst forms using the elements cobalt and titanium. The advantage of these elements is that they are much more abundant than the commonly used catalytic materials that contain precious metals such as iridium or ruthenium.
“The new process involves the creation of active catalytic sites at the atomic level on the surface of titanium oxide nanocrystals, a technique that produces durable catalytic materials and one of the best in triggering the reaction of oxygen evolution.” Zhang said. “A new approach to the catalyst of effective oxygen evolution catalysts and a better understanding of the basics for them is key to enabling a possible transition to scalable solar energy-use scales. This work is a perfect example of how to optimize catalyst efficiency for clean energy technologies by setting up nanomaterials. on an atomic scale. “
According to Gunnoe, “This innovation, centered on the achievements of the Zhang lab, represents a new method of improving and understanding catalytic materials with the resulting efforts involving the integration of advanced material synthesis, atomic level characterization and quantum mechanics theory.”
“A few years ago, UVA joined the MAXNET Energy Consortium, made up of eight Max Planck Institutions (Germany), UVA and the University of Cardiff (UK), which unites international collaboration efforts focused on electrocatalytic water oxidation. My group and Zhang’s laboratory, which has been and continues to be a productive and productive collaboration, “said Gunnoe.
With the help of the Argonne National Laboratory and the Lawrence Berkeley National Laboratory and the state-of-the-art X-ray sinchrotron absorption spectroscopy facility, which uses radiation to examine the structure of matter at the atomic level, the research team found that the catalyst had a defined surface structure that allowed them to see clearly how catalysts evolve at the time of oxygen evolution reaction and allow them to accurately evaluate its performance.
“X-ray work from Advanced Photon Source and Advanced Light Source is part of a ‘quick access’ program provided for quick feedback loops to explore emerging or pressing scientific ideas,” said Argonne X- Hua ray physicist Zhou, co-author of the paper. “We are delighted that both national scientific user facilities can substantially contribute to better and cleaner work in the water split that will provide a foregleam for clean energy technology.”
Both Advanced Photon Source and Advanced Light Source are the U.S. Department of Energy (DOE) Office of Applied Science Facilities located at the Argonne DOE National Laboratory and Lawrence Berkeley National Laboratory.
In addition, researchers at Caltech, using the latest quantum mechanics methods can accurately predict the level of oxygen production caused by catalysts, which provides a detailed understanding of the chemical mechanisms of their reactions.
“We have developed new quantum mechanics techniques to understand the mechanism of oxygen evolution reaction for more than five years, but in all previous studies, we have not been able to determine the exact catalyst structure. Zhang Catalyst has a proper atomic structure, and we find that our theoretical output , in essence, is in agreement with the results of experimental research, “said William A. Goddard III, professor of chemistry, materials science, and applied physics at Caltech and one of the project’s leading investigators. “This provides strong initial experimental validation of our new theoretical method, which can now be used to predict better catalysts that can be synthesized and tested. This is an important milestone for global clean energy.”
“This work is a good example of the team’s efforts by UVA and other researchers to work on clean energy and attractive findings that come from this interdisciplinary collaboration,” said Jill Venton, chairman of UVA’s Department of Chemistry.
Papers of Zhang, Gunnoe, Zhou and Goddard were published on December 14, 2020, at Katalitian Alam, The author and paper is Chang Liu, UVA Ph.D. students in the Zhang group, and Jin Qian, Ph Caltech. students in the Goddard group. Other authors include Colton Sheehan, a UVA graduate student; Zhiyong Zhang, postdoctoral scholar UVA; Hyeyoung Shin, Caltech postdoctoral scholar; Yifan Ye, Yi-Sheng Liu and Jinghua Guo, three researchers at Lawrence Berkeley National Laboratory; Gang Wan and Cheng-Jun Sun, two researchers at the Argonne National Laboratory; and Shuang Li and Sooyeon Hwang, two researchers at Brookhaven National Laboratory. His research is supported by the National Science Foundation and the U.S. Department of Energy-funded user facilities.
References: “Oxygen evolutionary reaction in Co-site catalytic on surface of TiO2 brookite nanorod surface is clear” by Chang Liu, Jin Qian, Yifan Ye, Hua Zhou, Cheng-Jun Sun, Colton Sheehan, Zhiyong Zhang, Gang Wan, Yi -Sheng Liu , Jinghua Guo, Shuang Li, Hyeyoung Shin, Sooyeon Hwang, T. Brent Gunnoe, William A. Goddard III and Sen. Zhang, December 14, 2020, Katalitian Alam,
DOI: 10.1038 / s41929-020-00550-5