A review of transition metal compounds-carbon hybrid electrocatalysts for sustainable hydrogen production through water splitting

Abstract Designing efficient, affordable, and durable electrocatalysts to drive water splitting is crucial for addressing the energy crisis and environmental issues. Transition metal-based materials are widely used for hydrogen and oxygen evolution reactions due to their tunable activity and abundance. However, challenges like low conductivity, agglomeration, and poor stability persist. Transition metal compounds have the potential to provide a solution by integrating carbon materials. This review examines the integration of transition metal compounds (TMCs) with carbon nanofibers (CNFs) and carbon nanotubes (CNTs) to enhance the efficiency of electrochemical water splitting, a vital process for sustainable hydrogen production. The mechanisms of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are discussed, emphasizing the role of electrocatalysts in mitigating overpotentials associated with these reactions. TMCs, when combined with CNFs and CNTs, create synergistic effects that improve reaction kinetics and increase active sites for catalysis. This review highlights recent advancements in the development of hybrid nanocomposites, detailing how their unique physicochemical properties facilitate effective electron transfer and enhance electrocatalytic activity and the stability of these integrated materials under harsh electrochemical conditions. Through a comprehensive examination of recent studies, this review aims to provide insights into the design and optimization of advanced electrocatalysts for efficient water splitting.