Selective electrocatalytic CO2 reduction enabled by SnO2 nanoclusters

Abstract The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO 2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective production is often challenging. Tin based-materials have attracted great attention for formate production, and yet their performances are far from satisfactory. In this study, we reported the preparation of SnO 2 nanoclusters from the controlled self-polymerization of dopamine together with SnO 3 2− , followed by the mild-temperature calcination. The final product consisted of large primary particles that were further made of small secondary SnO 2 nanocrystals. When evaluated as the electrocatalyst for CO 2 reduction in 0.5 M NaHCO 3 , our material exhibited impressive activity, selectivity and stability for the selective CO 2 reduction to formate. A peak formate Faradaic efficiency of ∼73% and large partial current density of 16.3 mA/cm 2 was achieved at -0.92 V versus reversible hydrogen electrode.