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

摘要

High surface area tin oxide nanocrystals prepared by a facile hydrothermal method are evaluated as electrocatalysts toward CO_2 reduction to formate. At these novel nanostructured tin catalysts, CO_2 reduction occurs selectively to formate at overpotentials as low as ～340 mV. In aqueous NaHCO_3 solutions, maximum Faradaic efficiencies for formate production of ＞93% have been reached with high stability and current densities of ＞10 mA/cm~2 on graphene supports. The notable reactivity toward CO_2 reduction achieved here may arise from a compromise between the strength of the interaction between CO_2~(·-) and the nanoscale tin surface and subsequent kinetic activation toward protonation and further reduction.