Selective electroreduction of carbon dioxide to formic acid on electrodeposited SnO_2@N-doped porous carbon catalysts

Electrocatalytic reduction of CO_2 is a promising route for energy storage and utilization. Herein we synthesized SnO_2 nanosheets and supported them on N-doped porous carbon (N-PC) by electrodeposition for the first time. The SnO_2 and N-PC in the SnO_2@N-PC composites had exellent synergistic effect for electrocatalytic reduction of CO_2 to HCOOH. The Faradaic efficiency of HCOOH could be as high as 94.1% with a current density of 28.4 mA cm-2 in ionic liquid-MeCN system. The reaction mechanism was proposed on the basis of some control experiments. This work opens a new way to prepare composite electrode for electrochemical reduction of CO_2.