Enhanced catalytic activity and stability of bismuth nanosheets decorated by 3-aminopropyltriethoxysilane for efficient electrochemical reduction of CO2

Herein, the effects of the introduction of 3-aminopropyltriethoxysilane (APTES) on the intrinsic properties of functionalized Bi nanosheets (Bi-NHS) electrocatalyst and the electrocatalytic performance of CO2 reduction reaction were carefully studied. As a result, high selectivities (> 90 %) to formate in significantly wide potentials of 500 mV and the energy efficiency Phi(HCOOH) as high as 65.8 % at -0.66 V for the cathodic half reaction can be observed. In addition, the Bi-NHS electrode shows a maximal faradic efficiency of 96.0 % at -0.96 V and a low overpotential around 340 mV, maintains well-preserved catalytic activity, giving formate yield of 8.02 g L-1, in a long term of continuous electrolysis. Based on experiment and density functional theory (DFT) calculations, CO2 reduction to formate on Bi(001)-NHS surface is more energetically favorable than that on bare Bi(001) surface and the APTES is excellent ligands as promoters for stabilized catalytic performance of metallic bismuth.

Automated summary

The introduction of APTES has significant effects on the properties of the Bi-NHS catalyst and the electrocatalytic performance for CO2 reduction, leading to high selectivity and efficiency.