Vanadium changes the local electron densities of InNNi3−xVx for highly efficient and selective electrocatalytic CO2 reduction to formate

Electroreduction of CO 2 into beneficial products is integral to attaining carbon neutrality. Herein, we detail a series of anti-perovskite nitrides InNNi 3− x V x ( x = 0, 0.2, 0.4, 0.6, 0.8) to be highly effective CO 2 RR. The InNNi 2.4 V 0.6 demonstrated exceptional conversion of CO 2 to formate, achieving an optimal Faraday efficiency (FE) of 93.6 % at −0.754 V versus RHE. It also exhibited a partial current density of 200 mA cm −2 at −1.1 V versus RHE, along with remarkable stability in an H-type cell. Electrochemical tests, X-ray absorption fine structure, and theoretical calculations demonstrated that in addition to altering InNNi 3 electronic structure, V doping results in lattice distortion in NiN 3 octahedron, increasing the lattice spacing of InNNi 2.4 V 0.6 (111) surface, exposing more active sites. This enhances its ability to adsorb the reaction intermediate *OCHO, thereby facilitating the conversion of CO 2 into formate. This research offers a viable approach for optimizing an electrocatalyst to convert CO 2 to valuable products.