Fluorine Doped Cagelike Carbon Electrocatalyst: An Insight into the Structure-Enhanced CO Selectivity for CO2 Reduction at High Overpotential.

The critical bottleneck of electrocatalytic CO2 reduction reaction (CO2RR) lies in its low efficiency at high overpotential caused by competitive hydrogen evolution. It is challenging to develop an efficient catalyst achieving both high current density and high Faradaic efficiency (FE) for CO2RR. Herein, we synthesized fluorine-doped cagelike porous carbon (F-CPC) by purposely tailoring its structural properties. The optimized F-CPC possesses large surface area with moderate mesopore and abundant micropores as well as high electrical conductivity. When used as catalyst for CO2RR, F-CPC exhibits FE of 88.3% for CO at -1.0 V vs RHE with a current density of 37.5 mA·cm -2. Experimental results and finite element simulations demonstrate that the excellent CO2RR performance of F-CPC at high overpotential should be attributed to its structure-enhanced electrocatalytic process stemming from its cagelike morphology.