Dynamic Metal-Ligand Coordination Boosts CO2 Electroreduction

The interfacial structure of heterogeneous catalystsdeterminesthe reaction rate by adjusting the adsorption behavior of reactionintermediates. Unfortunately, the catalytic performance of conventionallystatic active sites has always been limited by the adsorbate linearscaling relationship. Herein, we develop a triazole-modified Ag crystal(Ag crystal-triazole) with dynamic and reversible interfacialstructures to break such a relationship for boosting the catalyticactivity of CO2 electroreduction into CO. On the basisof surface science measurements and theoretical calculations, we demonstratedthe dynamic transformation between adsorbed triazole and adsorbedtriazolyl on the Ag(111) facet induced by metal-ligand conjugation.During CO2 electroreduction, Ag crystal-triazolewith the dynamically reversible transformation of ligands exhibiteda faradic efficiency for CO of 98% with a partial current densityfor CO as high as -802.5 mA cm(-2). The dynamicmetal-ligand coordination not only reduced the activation barriersof CO2 protonation but also switched the rate-determiningstep from CO2 protonation to the breakage of C-OHin the adsorbed COOH intermediate. This work provided an atomic-levelinsight into the interfacial engineering of the heterogeneous catalyststoward highly efficient CO2 electroreduction.

Automated summary

The structure of heterogeneous catalysts at the interface directly affects the reaction rate by controlling the adsorption behavior of reaction intermediates. In this study, a triazole-modified silver crystal (Ag crystal-triazole) with dynamic and reversible interface structures was developed to enhance the catalytic activity in the electroreduction of CO2 to CO. Through surface science measurements and theoretical calculations, the researchers demonstrated the dynamic transformation between adsorbed triazole and adsorbed triazolyl on the Ag(111) facet induced by metal-ligand conjugation. The dynamic metal-ligand coordination not only reduced the activation barriers but also altered the rate-determining step, leading to highly efficient CO2 electroreduction.