Gold-Supported Gadolinium Doped CoB Amorphous Sheet: A New Benchmark Electrocatalyst for Water Oxidation with High Turnover Frequency

Electrochemical water splitting has been considered a promising approach for green and sustainable hydrogen as a future energy carrier. However, the lack of high performance and inexpensive electrocatalysts for kinetically sluggish oxygen evolution reaction (OER) hinder the practical application. Here, the noteworthy enhancement of electrodeposited cobalt boride (CoB) nanosheets from the combined effect of using gadolinium as a dopant and thin film of gold as prudent support is demonstrated. The free-standing Gd-CoB@Au exhibits remarkable electrochemical performance, high intrinsic activity, and lower reaction resistance, which are confirmed by lower onset potential, small charge transfer resistance, lower Tafel slope value, and high turnover frequency. Furthermore, the post-OER characterization signpost, no observable change in the chemical structure or morphology of nanosheets during the long-lasting oxidation process. Because of the inexpensive, facile, and scalable one-step preparation processes, the catalyst is highly encouraging for large-scale practical applications.