Advances in nonprecious metal catalysts for efficient water oxidation in alkaline media

Fossil fuels are facing various challenges, such as global warming and depletion of fossil energy sources. Fortunately, hydrogen energy can be a green energy source for sustainable development. Hydrogen production from electrolytic water is one of the most efficient methods in the hydrogen energy industry; however, the realization of an efficient electrochemical oxygen evolution reaction (OER) is the key to hydrogen production from electrolytic water. As a result, developing noble metal-free electrocatalysts with high activity and alkaline stability is critical. This article gives a focused evaluation of the most recent highly active oxygen evolution catalysts in this new research field. The mechanism of the OER catalyst in an alkaline environment is discussed first, followed by the fundamental needs of catalysts for the oxygen evolution process. Then, contemporary researchers’ design alternatives for enhancing OER active materials are explored, as well as new developments and discoveries of current advanced noble metal-free active materials. Finally, the problems and future prospects for developing efficient catalyst systems for industrial applications are discussed. Future research directions are also pointed out for the preparation of resource-rich emerging nonprecious metal OER electrocatalysts in alkaline environments.