HIGH-ENTROPY NIFECOCUW LAYERED DOUBLE HYDROXIDE PROMISES ADVANCED OXYGEN EVOLUTION IN ALKALINE WATER AND ALKALINE SEAWATER

Abstract

Water/seawater electrolysis is considered a pivotal technological route toward scalable and eco-friendly hydrogen generation and is recognized as a promising renewable alternative to conventional fossil fuels. Herein, high-entropy NiFeCoCuW layered double hydroxide (LDH) flower-like microspheres are fabricated via a facile one-pot hydrothermal strategy as efficient and stable oxygen evolution catalyst. An overpotential of only 118 mV is required for the as-prepared NiFeCoCuW-LDH catalyst to achieve a current density of 10 mA cm^-2 in alkaline water, highlighting its exceptional oxygen evolution reaction (OER) performance. In alkaline seawater (1 M KOH + seawater), the catalyst achieves an OER overpotential of 122 mV at 10 mA cm^-2, while retaining satisfactory electrocatalytic activity. The NiFeCoCuW-LDH catalyst fabricated in this work not only possesses the superior catalytic activity and low cost of transition metal-based catalysts, but also exhibits the flexible electronic regulation capability and multimetal synergistic effects of high-entropy materials, which endows the catalyst with exceptional electrocatalytic performance.

Keywords:
high-entropy; layered double hydroxide; oxygen evolution reaction; water splitting; seawater electrolysis.