Preparation of phosphorus-doped Cu-based catalysts by electrodeposition modulates *CHxO adsorption to facilitate electrocatalytic reduction of CO2 to CH4

Catalysts for the generation of methane in electrochemical CO reduction reactions (CORR) must have suitable adsorption energies for the intermediate products. In this study, we used a one-step electrodeposition method to prepare nitrogen(N) and phosphorus(P)-doped copper(Cu)-based catalysts. The introduction of P to the catalyst resulted in a significant change in the CORR pathway, leading to efficient and highly selective methane production. The Cu-N-P electrocatalyst exhibits a CH Faradaic efficiency (FE) of 73 % at a potential of −1.6 V vs RHE, and it was found to be more effective in promoting the hydrogenation process of *CHO-*CHO-*CHO, which was confirmed by in-situ IR, X-ray absorption techniques and DFT calculations. P serves as the primary electron donation site in the catalyst, thereby influencing the charge distribution properties of the surrounding Cu atoms. This, in turn, facilitates the regulation of intermediate adsorption, representing the primary factor in the notable enhancement of methane selectivity.