Exploring the Role of CoTe/Co₃O₄ Composite Catalyst for Enhanced Oxygen Evolution Reaction

Abstract

We prepared a cobalt oxide composite with cobalt telluride (CT@CO) via a hydrothermal approach, and this material acts as a highly active and durable electrocatalyst for the oxygen evolution reaction. The X-ray studies reveal that a spinel phase of cobalt oxide and a hexagonal phase of cobalt telluride have been formed. The field emission scanning electron microscopy (FESEM) study shows that cobalt telluride has nanosheet morphology, and a nanorod morphology has been obtained for cobalt oxide. X-ray photoelectron spectroscopy and Raman spectroscopy also confirm the successful interaction between Co 3 O 4 and CoTe. This CoTe/Co 3 O 4 (CT@CO sample) nanosheet-nanorod-shaped catalyst shows excellent OER performance compared with its constituent. It generates a current density of 10 mA/cm 2 at a low overpotential of 287 mV and Tafel slope (69 mV/dec). The electrochemical impedance spectroscopy (EIS) study reveals that the composite has the smallest charge transfer resistance than others. These findings suggest that CoTe/Co 3 O 4 (CT@CO) composite has a promising catalytic property for efficient OER generation. density functional theory (DFT) studies have also been performed, and the theoretical findings agree well with the experimental result.