Co3O4 Hybrid Electrocatalysts; Materials Description and Mechanistic Aspects Toward Hydrogen Production, Oxygen Evolution-Reduction, and CO2 Reduction Reactions

Controlling the adverse effects of global warming on human communities requires reducing carbon dioxide emissions and developing clean energy resources. Fossil fuel overuse damages the environment and raises sustainability concerns. As a resource-rich element, cobalt oxide hybrids have attracted considerable attention as low-priced and eco-friendly electrocatalysts. Alkaline solutions disperse Co3O4 easily despite its highly stable nature, which arises from the reverse spinel structures of Co. Metal oxides, nickel foam, polymeric frameworks, and carbon nanotubes have been successfully served to combine with the Co3O4 constructions for improving the electrocatalytic performance. To date, no comprehensive study has systematically investigated the relation between the cobalt oxide hybrid's physicochemical-electronic aspects and its catalytic features. This review mainly focuses on material design, fabrication, morphology, structural characteristics, and electroactivity, considering the critical factors towards practical applications. The economic impacts of the constructions and their expected contribution to large-scale utilizations are also demonstrated. Moreover, this research discusses the synergistic effects of crucial electrochemical parameters on sustainable energy production over the Co3O4-based hybrids. Finally, some beneficial conclusive suggestions are made based on emerging factors for real-world application. Future research in the field aiming at developing sustainable and clean energy production technologies can effectively benefit from the findings of this report.