Nanostructured Tin Catalysts for Selective Electrochemical Reduction of Carbon Dioxide to Formate.

High surface area tin oxide nanocrystals prepared by a facile hydrothermal method are evaluated as electrocatalysts toward CO2 reduction to formate. At these novel nanostructured tin catalysts, CO2 reduction occurs selectively to formate at overpotentials as low as ~340 mV. In aqueous NaHCO3 solutions, maximum Faradaic efficiencies for formate production of >93% have been reached with high stability and current densities of >10 mA/cm2 on graphene supports. The notable reactivity toward CO2 reduction achieved here may arise from a compromise between the strength of the interaction between CO2•– and the nanoscale tin surface and subsequent kinetic activation toward protonation and further reduction. [ABSTRACT FROM AUTHOR]