High-entropy (Oxy)hydroxide Prepared by Electrodeposition for Highly Efficient OER in Alkaline Medium

Abstract With the development of the economy and society, energy shortage and environmental pollution are increasingly in the spotlight. Electrolytic water to hydrogen technology is considered to be the best way to produce green hydrogen. However, the slow thermodynamic/kinetic limitations make it difficult to scale application due to an anodic oxygen evolution reaction (OER) involving four electrons. Recently, transition metal-based materials become popular research subjects because properties of abundant reserve and low cost. Fortunately, the performances for water splitting are surprising compared to some noble metal-based materials which means these materials have huge potential for practical application in reality. The transition metal (oxy)hydroxides are confirmed to be a category of promising electrocatalysts for OER. To improve the activity of catalysts, many effective strategies (including defects engineering, vacancy engineering, interface engineering, high-entropy effect, etc.) are adopted to modulate the electronic structure and enrich active site density. In this work, we have successfully synthesized high-entropy transition metal (oxy)hydroxides by one-step electrodeposition for water oxidation. The results obtained confirmed the high-entropy effect results in high intrinsic activity and high stability for electrochemical water oxidation.