Tuning Layered Double Hydroxides from Trimetallic to High-Entropy Nanomaterials for Enhanced Oxygen Evolution in Alkaline Environments

Layered double hydroxides (LDHs) enriched with multiple metal elements and high-entropy alloys (HEAs) have gained attention as effective catalysts for the oxygen evolution reaction (OER). In this study, we report the hydrothermal synthesis of high-entropy FeCoCrMnCu (FCCMC) LDHs, aiming to develop cost-efficient and durable electrocatalysts. Extensive material characterization using FE-SEM, HR-TEM, XRD, EDX, and XPS confirmed the successful fabrication of FCCMC LDHs with uniform elemental dispersion and well-defined crystal structure. When tested under alkaline conditions, FCCMC LDHs displayed superior OER performance compared to their ternary (FeCoCr, FCC) and quaternary (FeCoCrMn, FCCM) analogs. Specifically, FCCMC achieved a notably low overpotential of 295 mV at 10 mA cm^–2 and a Tafel slope of 119.5 mV dec^–1, suggesting more favorable catalytic kinetics. Moreover, the FCCMC catalyst demonstrated impressive operational stability, maintaining activity over 74 h without significant performance loss. Collectively, these results identify FCCMC LDHs as a highly promising candidate for advancing efficient and stable electrocatalysts, supporting future progress in clean and sustainable energy technologies.