Unveiling the mechanism of electrocatalytic oxidation of glycerol by in-situ electrochemical spectroscopy

The electrocatalytic glycerol oxidation reaction (GOR) is an efficient way to reduce the overpotential of the anodic reaction of electrocatalytic water splitting with abundant high-value byproducts. However, it has always been difficult to reveal a clear reaction path and real active site during the electrocatalytic glycerol oxidation reaction (GOR) process. In this work, NiOOH/Ni3S2/NF, a model catalyst was synthesized by the two-step method, and the reaction path of the electrocatalytic oxidation of glycerol on NiOOH/Ni3S2/NF was clearly unveiled by the in situ infrared and Raman analysis. In addition, the TEM after GOR and in-situ Raman intuitively demonstrated that the NiOOH was the real active site during the GOR process. Consequently, the synthesized NiOOH/Ni3S2/NF catalyst achieved a current density of 10 mA cm-2 at 1.227 V vs. RHE and obtained a high formic acid Faraday efficiency of 97.7 % at a low potential of 1.4 V vs. RHE. This work demonstrates an effective method for unveiling the GOR mechanism and the other relevant electrocatalytic reaction processes.