Ordered cone−structured tin directly grown on carbon paper as efficient electrocatalyst for CO2 electrochemical reduction to formate

Abstract The conversion of carbon dioxide to chemicals by the electrochemical reactions (ERC) is an efficient solution to the current energy crisis and excess CO2 emissions. It is still a great challenge and of significance to synthesize a highly selective, efficient, and non−noble metal electrocatalyst that facilitates the ERC reaction. A novel triton X−100 (C14H22O(C2H4O)n) assisted electrodeposition method was developed to synthesize the ordered cone−structured tin (OCSn) electrocatalysts with controllable morphology and structure. The results suggest that Triton X−100 plays an important role in directing the structure of the Sn electrocatalysts during the electrodeposition process. The OCSn synthesized at 60 mA cm−2 achieves the best performances. It selectively catalyzes the ERC on the onset potential about 110 mV lower than Sn synthesized without Triton X−100. In 0.5 M NaHCO3, high faradaic efficiency (92%) for formate product on OCSn has been achieved. More prominently, the catalyst presents excellent stability, showing no performance deterioration during 30 h electrolysis. This work provides an efficient, green, and scalable synthesis method of the electrocatalyst for CO2 reduction to formate.