Dual morphology ZnCo2O4 coupled graphitic carbon nitride: An efficient electro-catalyst for electrochemical H2O2 production and methanol oxidation reaction

Abstract

Dual morphology in ZnCo2O4 can be a fascinating trend; the same was coupled with graphitic carbon nitride (g-C3N4) via the facile hydrothermal method. The developed electro-catalyst is confirmed with various material characterizations technique and targeted for two applications such as electrochemical hydrogen peroxide (H2O2) synthesis and Methanol oxidation reaction (MOR). As dual morphology exhibits more active sites, kinetic studies and electrochemical surface active (ECSA) sites measurement are carried out. Kinetic studies are studied, and which diffusion coefficient is found to be up to 6.3 × 10−5 cm2/sec of ZnCo2O4/g-C3N4 composite. It exhibited 1.7 and 1.2 times more than Co3O4 and ZnCo2O4, respectively. ECSA is 14 cm2 for ZnCo2O4/g-C3N4, and these electrochemical properties clarified the application target. In the electrochemical H2O2 synthesis, the developed ZnCo2O4/g-C3N4 composite electro-catalyst delivered an excellent electron transfer number of 2.30, higher H2O2 selectivity % of 86.74 % at 0.55 V vs. RHE. For methanol oxidation reaction studies, ZnCo2O4/g-C3N4 composite electro-catalyst had a higher tendency of 162.5 mA/cm2 (scan rate 10 mV/sec) in the optimized alkaline-based electrolyte. Also, the developed electro-catalyst delivered excellent stability of 96.5 %, reducing CO poisoning from the electro-catalyst surface.