Laser-fabricated channeled Cu6Sn5/Sn as electrocatalyst and gas diffusion electrode for efficient CO2 electroreduction to formate

Formate synthesis by CO 2 electroreduction reaction (CO 2 RR) has been considered as a promising strategy for mitigating the excessive CO 2 . Here, we synthesize Cu 6 Sn 5 alloy on Sn foil (Cu 6 Sn 5 /Sn) and gas diffusion electrode (GDE) using laser irradiation. Cu 6 Sn 5 /Sn exhibits high formate faradaic efficiency (FE formate ) of 87.2% and remains stable at 28.69 mA cm −2 over 14 h. Further, with the help of laser drilling, the channeled Cu 6 Sn 5 /Sn used directly as GDE shows increased current density (118 mA cm −2 ) and steady FE formate (86.69%) in flow cell. Density functional theory (DFT) calculations reveal that the high performance of Cu 6 Sn 5 /Sn benefits from the appropriate binding energy of the key intermediates *OCHO. Meanwhile, COMSOL simulation results of CO 2 concentration and electric field distribution combined with the results of kelvin probe force microscopy (KPFM) prove that CO 2 RR prefers to occur around the channels of electrode. More importantly, this laser irradiation method is also available to synthesize other alloy electrocatalysts. • Cu 6 Sn 5 alloy were synthesized through laser irradiation. • The channeled Cu 6 Sn 5 /Sn prepared by laser drilling could directly use as GDE, and the current density increased 4-fold. • The enhanced CO 2 electroreduction performance was revealed by COMSOL Multiphysics simulation and KPFM.