Cu(OH) 2 @MoO 3 Nanorod Heterostructure for Efficient Overall Electrocatalytic Water Splitting in an Alkaline Medium

The rational design of cost-effective electrocatalysts with superior catalytic activity for overall water splitting (OWS) continues to pose a significant challenge. The combination of oxygen vacancies and the adaptable electronic structure in the Cu(OH)2 heterostructure has made them highly appealing for catalytic applications. Herein, the Cu(OH)2 and MoO3 (Cu@MoO3) nanorod heterostructure was prepared via a simple hydrothermal process. Subsequently, Cu(OH)2 was anchored into the MoO3 nanorods using a coprecipitation method. The X-ray photoelectron spectroscopy result confirmed the existence of mixed Mo5+ and Mo6+ oxygen states and oxygen vacancies in the Cu@MoO3 heterostructure. The Cu@MoO3-3 electrocatalyst exhibited outstanding hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance, requiring overpotentials of 78 and 308 mV at 10 mA cm-2 in 1 M KOH, respectively. The constructed electrolyzer exhibits impressive durability, achieving 10 mA cm-2 at 1.56 V along with a Faradaic efficiency of 86.44% for O2 production. This study demonstrates the successful synthesis of a catalyst via a hydrothermal process, highlighting its promising potential for future applications.