by Staff Writers
Washington DC (SPX) Apr 12, 2017
A "self-heating" boron catalyst that makes particularly efficient use of sunlight to reduce carbon dioxide (CO2) serves as a light harvester, photothermal converter, hydrogen generator, and catalyst in one. In the journal Angewandte Chemie, researchers introduce a photothermocatalytic reaction that requires no additives beyond water. This could form the basis of a new, more efficient process for converting the greenhouse gas CO2 into a useful carbon source for the production of fuels and chemical products.
The ideal route for making CO2 useful is considered to be reduction aided by a photocatalyst to use sunlight as the only source of energy - a process that corresponds to the first step of photosynthesis. Despite decades of research, processes for converting CO2 are still too inefficient. "This is largely due to the insufficient utilization of solar light, the high energy barrier for CO2 activation, and the sluggish kinetics of the multiple electron and proton transfer processes," explains Jinhua Ye.
Working with a team for the National Institute for Materials Science (NIMS) in Tsukuba, Ibaraki, and Hokkaido University in Sapporo (Japan), as well as Tianjin University and Nanjing University of Aeronautics and Astronautics (China), Ye is now pursuing a strategy that uses both the light and thermal energy provided by sunlight. When the sun shines on a surface, it is heated. The researchers want to use this ordinary photothermic effect to increase the efficiency of catalytic systems.
Their material of choice is powdered elemental boron, which very strongly absorbs sunlight and efficiently converts it photothermically, heating itself up remarkably. This allowed the team to carry out the efficient reduction of CO2 to form carbon monoxide (CO) and methane (CH4) under irradiation in the presence of water, with no additional reagents or co-catalysts.
Irradiation causes the boron particles to heat up to about 378 C. At this temperature it reacts with water, forming hydrogen and boron oxides in situ.
The boron oxides act as "traps" for CO2 molecules. The hydrogen is highly reactive and, in the presence of the light-activated boron catalyst, efficiently reduces the CO2 by providing the necessary protons (H+) and electrons.
"The key to our success lies in the favorable properties of the boron powder, which make it an all-in-one catalyst: light harvester, photothermic converter, hydrogen source, and catalyst," says Ye.
"Our study confirms the highly promising potential of a photothermocatalytic strategy for the conversion of CO2 and potentially opens new vistas for the development of other solar-energy-driven reaction systems."
Vienna, Austria (SPX) Apr 12, 2017
Diamonds with minute flaws could play a crucial role in the future of quantum technology. For some time now, researchers at TU Wien have been studying the quantum properties of such diamonds, but only now have they succeeded in coupling the specific defects in two such diamonds with one another. This is an important prerequisite for the development of new applications, such as highly sensi ... read more
Carbon Worlds - where graphite, diamond, amorphous, fullerenes meet
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|