Aligned InS Nanorods for Efficient Electrocatalytic Carbon Dioxide Reduction.

Electrochemical CO reduction technology can combine renewable energy sources with carbon capture and storage to convert CO into industrial chemicals. However, the catalytic activity under high current density and long-term electrocatalysis process may deteriorate due to agglomeration, catalytic polymerization, element dissolution, and phase change of active substances. Here, we report a scalable and facile method to fabricate aligned InS nanorods by chemical dealloying. The resulting aligned InS nanorods exhibit a remarkable CORR activity for selective formate production at a wide potential window, achieving over 90% faradic efficiencies from -0.5 to -1.0 V vs reversible hydrogen electrode (RHE) under gas diffusion cell, as well as continuously long-term operation without deterioration. In situ electrochemical Raman spectroscopy measurements reveal that the OCHO species (Bidentate adsorption) are the intermediates that occurred in the reaction of CO reduction to formate. Meanwhile, the presence of sulfur can accelerate the activation of HO to react with CO, promoting the formation of OCHO intermediates on the catalyst surface. Significantly, through additional coupling anodic methanol oxidation reaction (MOR), the unusual two-electrode electrolytic system allows highly energy-efficient and value-added formate manufacturing, thereby reducing energy consumption.