Promotion of electrochemical CO2 reduction to ethylene on phosphorus-doped copper nanocrystals with stable Cuδ+ sites

Electrochemical reduction of CO2 to C2+ products is a sustainable energy-driven pursuit for high added-value hydrocarbons. Tremendous efforts have been made to copper based electrocatalysts, which are well-known for producing C2+ products. However, being short of well-defined catalysts with stable Cuδ+ electronic structure hinders its practical application and in-depth understanding. Herein, we developed a facile one-pot approach to prepare Cuδ+-rich catalyst by doping phosphorus. Enhanced performance and tunable product selectivities are achieved due to the electron donor–acceptor interaction based on phosphorus content in series. C2 hydrocarbons and alcohols are produced with high (~44.9%) selectivity, in which C2H4 (30.7 ± 0.9%) is dominant at −1.6 V vs reversible hydrogen electrode (RHE). This P-Cu catalyst shows a significantly higher current density (57.2 mA cm−2) compared to pristine Cu. In addition, the favorable Cuδ+ is reserved during CO2RR contributing to a long-term stability. Experimental results and DFT calculations demonstrate that the Cuδ+ moiety facilitates the adsorption of carbon intermediates, C-C coupling and hence promotes the generation of C2H4 energetically. The well-designed catalyst indicates the profit of electronic structure engineering in designing catalysts for multiple-step chemical conversions.