A fast, efficient, and abundant catalyst for carbon dioxide reduction
A tungsten carbide catalyst can produce a hydrocarbon from carbon dioxide at high rates and high efficiency
image: A catalyst made of di-tungsten carbide (center) can reduce carbon dioxide (CO2) to make the hydrocarbon methane (CH4) and potentially other products (right). It can be tuned to selectively produce CH4 as the main product (maroon filled circle in inset).
Credit: Image courtesy of Lawrence Berkeley National Laboratory
The Science
Catalysts speed up chemical reactions. They are key players in many clean-energy technologies, including turning carbon dioxide (CO2) into useful fuel products. A team of researchers investigated a catalyst made of di-tungsten carbide (W2C). This catalyst consists of elements that are abundant on Earth, tungsten and carbon. The research demonstrated that the catalyst can produce methane from CO2 at high rates and high efficiency and can provide insights for selective fuel production.
The Impact
This work demonstrated that a highly active catalyst made of abundant raw materials could selectively produces useful hydrocarbons. The catalytic conversion process of CO2 to primarily CH4 could provide a foundation for development of future catalysts for low-cost, sustainable, and effective large-scale production of fuels from CO2.
Summary
One possible solution to the problem of rising CO2 levels in the atmosphere is to capture it and turn it into useful chemical compounds. However, turning CO2 into hydrocarbon products is costly and slow. Catalysts speed up chemical reactions and are key players in many clean-energy technologies. Thus far, researchers have found that current catalysts can either produce useful products or perform quickly and easily, but not both. A team of researchers working at the Molecular Foundry at Lawrence Berkeley National Laboratory investigated a set of transition metal carbide catalysts and discovered that di-tungsten carbide (W2C), in particular, works remarkably well. Density functional theory simulations conducted by the research team revealed that the key limiting steps in reducing CO2 (water dissociation, CO2 chemisorption, and C-O bond cleavage) are nearly spontaneous when W2C is used as a catalyst.
The catalysts typically used to try to speed up CO2 reduction are either very expensive, relying on pure, rare metals like gold or palladium (a critical material), or require extremely high amounts of energy to function. The W2C catalyst studied here is made of inexpensive, common earth-abundant elements and could provide insights for low-cost, sustainable large-scale production of fuels from CO2.
Funding
Support for this research included funding and resources from Illinois Institute of Technology, Northwestern University, University of Illinois at Chicago, the State of Illinois, the National Science Foundation, the Wanger Institute for Sustainable Energy Research (WISER), and the American Institute of Architects (AIA) Upjohn Development Research Grant. This work was performed at the Molecular Foundry, a Department of Energy (DOE) Office of Science user facility, and its compute cluster (Vulcan) operated by Lawrence Berkeley National Laboratory and by the National Energy Research Scientific Computing Center (NERSC), another DOE Office of Science user facility.