High surface area tin oxide nanoparticles prepared by a facile hydrothermal method followed by electroreduction to tin act as electrocatalysts toward CO.sub.2 reduction to formate, in some embodiments. At certain of these nano-structured tin catalysts, CO.sub.2 reduction occurs selectively to formate at low overpotentials and with high Faradaic efficiencies, with high stability and significant current densities.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under Grant No. DE-SC0001011 awarded by the Department of Energy. The U.S. Government has certain rights in the invention.