Cobalt-Based Electrocatalysts for Water Splitting: An Overview

Recently, considering the increasing global energy demands and fossil fuel issues, many researchers have focused on designing and developing clean renewable energy systems. Electrolyzers as promising candidates for hydrogen production are of attractive interest, but the expensive noble-metal based catalysts are the main obstacle to their wide applications. Transition metal-based catalysts such as Co, Ni, Mn, and Fe have shown to be promising substitutes. Among them, Co-based catalysts are rapidly rising as highly efficient catalysts with diverse global study activities. In this review, we have summarized recent progress in Co-based materials as hydrogen evolution reaction and oxygen evolution reaction electrocatalysts from an electrocatalytic performance point-of-view, and also the approaches behind the enhanced electrocatalytic activities such as morphology and structure rational design, controlling the chemical composition, and hybridizing with carbonaceous supports.