Enhancing Stability and Activity of Transition Metal Chalcogenides: Development of Carbon-Based Hydrochar Supported Nickel-Cobalt Selenide Electrocatalyst for Oxygen Evolution Reaction

Abstract

Transition metal chalcogenides (TMCs) have been utilized as cost-effective alternatives for noble metal electrocatalysts, exhibiting comparable activity in the oxygen evolution reaction (OER). Nickel-cobalt selenide (NiCoSe) is a TMC exhibiting significant potential in reducing the overpotential of the oxygen evolution reaction (OER). A carbon-based hydrochar support is used as a scaffold for depositing NiCoSe, ensuring the dispersion and stability of the synthesized electrocatalyst. This work develops a NiCoSe/hydrochar electrocatalyst to enhance the stability and activity of the TMC towards OER. Various compositions of nickel-cobalt selenide (NiCoSe2, Ni0.85Co0.85Se, and Ni0.6Co0.4Se2) with a chitin-based hydrochar support are synthesized. The electrocatalytic activity is determined using cyclic voltammetry (CV) and linear sweep voltammetry using a three-electrode set-up. NiCoSe2 has the lowest overpotential at 179.3 mV and a Tafel slope of 163.4 mV-dec-1. This highlights the enhanced performance of NiCoSe2 compared to other compositions.