Hydrogenation of CO2to C 2+hydrocarbons over non-noble metal catalysts is essential from environmental and economic aspects.However,increasing the selectivity of C2 +hydrocarbons is still challenging for Co-based catalysts,as their predominant selectivity is toward CH4(>99%).Herein,this work provides insights into the mechanism of CO 2hydrogenation over a N-doped Co3O 4(CoN xO y)catalyst with a higher CO 2conversion(25%)and C 2+hydrocarbon selectivity(42 C-mol%)compared to the Co3O 4parent material(9%and 3 C-mol%,respectively).An increased concentration of oxygen vacancies and a decreased surface basicity strength in CoNxO ycorrelated with its enhanced catalytic performance.In situ diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculations revealed the evolution of reaction intermediates and the N-doping benefits on the CoNxO ycatalyst for high activity toward C 2+hydrocarbons.The findings were consistent with a CO 2hydrogenation catalytic cycle,where CO and C2 +hydrocarbons are mainly produced through carbonate and formate reaction pathways, respectively.Overall,we found that a relatively simple nitridation procedure can enhance the catalytic activity and selectivity of cobalt oxide toward higher hydrocarbons.This methodology could be extended to improve other transition metal-based catalysts for CO2conversion.