A new low-temperature catalyst produces high-purity hydrogen gas while simultaneously consuming carbon monoxide (CO) via the water-gas shift (WGS) reaction. The development by researchers from U.S. Department of Energy’s Brookhaven National Laboratory and Peking University, China, could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.
Brookhaven Lab chemists Ping Liu and José Rodriguez helped to characterize structural and mechanistic details of a new low-temperature catalyst. (Source: Brookhaven National Laboratory)
Because the catalyst operates at low temperature and low pressure to convert water and carbon monoxide to hydrogen gas and carbon dioxide, it could also lower the cost of running WGS reactions.
Gold nanoparticle clusters were synthesized on a molybdenum-carbide substrate to create an interfacial catalyst system for the ultra-low temperature WGS reaction. Water was activated over the catalyst at 303 Kelvins (30 C), while CO adsorbed on adjacent gold sites reacted with surface hydroxyl groups formed from water splitting — leading to high WGS activity at low-temperatures.
Structural studies were conducted using X-ray diffraction at the National Synchrotron Light Source while the catalyst was operating under industrial or technical conditions. These experiments revealed crucial details about how the structure changed under different operating conditions, including at different temperatures.
