▎ 摘　　要

Electrocatalytic reduction of CO2 to formate is an extremely attractive route. Here, we developed a SnSe2-gra-phene composite catalyst, and SnSe2 nanosheets were linked to graphene by Sn-O-C bonds to form complicated hierarchical nanosheet structure. Due to the intrinsic activity of SnSe2 and the modification of graphene, the catalyst performed excellent electrocatalytic efficacy for the reduction of CO2 to formate, with a maximum Faraday efficiency up to 95.1% at-0.9 V (vs. RHE) and a current density of 11.8 mA cm-2 under the optimal conditions. Kinetic experiments indicated that the SnSe2-graphene composite achieved efficient formate selec-tivity for CO2 reduction by increasing the initial transfer rate of electrons to the CO2 molecule.