Bismuth Catalyzes CO₂ Reduction

Inexpensive bismuth may soon give chemists a new option for dealing with carbon dioxide captured from industrial processes. Joel Rosenthal and coworkers at the University of Delaware have developed a non-precious-metal electrocatalyst that “efficiently and selectively reduces CO₂ to CO, which is an important energy-rich commodity chemical that can be used to synthesize liquid fuels,” Rosenthal says. Using bismuth(III) triflate as a precursor, the researchers electrodeposited amorphous bismuth metal on a carbon electrode under mild conditions. The bismuth catalyst achieves current densities that are an order of magnitude greater than existing silver and gold CO₂-reduction catalysts (J. Am. Chem. Soc. 2014, DOI: 10.1021/ja501923g). The high current density means that a device using the catalyst can churn out a large volume of CO per electrode area. Clifford P. Kubiak, an expert in catalytic CO₂ fixation at the University of California, San Diego, says that although challenges remain with the system, such as the high operating potential and the coproduction of water with the CO, “this is a very important contribution to the field of electrochemical reduction of CO₂.”