Surface Self‐Reconstruction of Fe‐Ni3S2 Electrocatalyst for Value‐Generating Nitrile Evolution Reaction to Drive Efficient Hydrogen Production

Abstract

AbstractThermodynamically favorable electrooxidation of organics coupled with hydrogen production as an alternative to overall water splitting is rapidly developing due to low energy consumption and high value. But understanding the relationship between catalyst reconstruction and performance in depth remains a challenge. Herein, DFT calculations are used as a theoretical guide to adjust the local coordination environment and electronic structure of Ni3S2 by Fe doping, which promotes the self‐reconstruction of catalyst and nitrile evolution reaction performance. The overall reaction of benzylamine electrooxidation coupled with hydrogen production achieves a 14.5‐fold improvement in hydrogen production compared to water electrolysis at the same potential, almost completely converting benzylamine to high‐value benzonitrile (99% product yield). In situ spectroscopy and X‐ray absorption fine structure spectroscopy demonstrate that the excellent electrocatalytic performance due to Fe doping induces surface self‐reconstruction of Ni3S2 to NiOOH at low potential, and significantly reduces the rate‐determining step energy barriers for CN bonds to CN bonds. This work provides theoretical guidance in designing and preparing efficient catalysts for the electrosynthesis of nitrile compounds coupled with hydrogen production.