Asymmetric Acetylene Activation Enables Enhanced Electrochemical Ethylene Formation Kinetics

Abstract Copper (Cu)‐based catalysts with weak ethylene (C 2 H 4 ) adsorption exhibit a robust ability to suppress the overhydrogenation of electrocatalytic acetylene (C 2 H 2 ) hydrogenation (EAH), providing a green alternative for C 2 H 4 production. However, the unsatisfactory C 2 H 4 formation kinetics due to the sluggishness of C 2 H 2 reactants still limit its practical application potential. Herein, borate‐decorated oxide‐derived copper nanoparticles (OD Cu–B NPs) are designed to promote C 2 H 2 activation and adsorption. As a result, the as‐prepared catalysts deliver a partial current density of 720 mA cm −2 with a turnover frequency of 48.33 s −1 , greatly outperforming the bare OD Cu counterpart. The symmetric electron distribution of C 2 H 2 is revealed to be broken over the Cu–borate interface, making it easier to activate and adsorb, which accounts for the lowered hydrogenation barrier and enhanced selectivity, consequently promoting C 2 H 4 formation kinetics through the EAH process.