BiPO4‐Derived 2D Nanosheets for Efficient Electrocatalytic Reduction of CO2 to Liquid Fuel

The electrochemical reduction of carbon dioxide (CO2) to high‐value liquid fuel with high selectivity is appealing for energy conversion and storage. Here we report a bismuth phosphate (BiPO4) derived 2D nanosheet‐like electrocatalyst that efficiently converts CO2 into liquid‐phase formate. The catalyst presents a formate Faradaic efficiency of over 90 % and a cathodic energy efficiency of 73 % at an industrially relevant current density of 200 mA cm−2 in the flow cell. The in situ generation of the Bi‐O active species on the catalyst surface was determined via operando Raman measurement. Morphological and X‐ray photoelectron spectroscopy analyses reveal the origin of the high activity for the electrosynthesis of formate from CO2 and water: the 2D structure together with the abundant insertion of oxygen atoms in the surface of the BiPO4‐derived nanosheets. The bismuth phosphate derived 2D nanosheet‐like catalyst exhibits a high formate cathodic energy efficiency of 73 % at a current density of 200 mA cm−2. The excellent catalytic performance is attributed to the 2D structure and abundant oxygen‐modified Bi active sites on the surface.