Material Science & Engineering World Conference 2026

Abstract

Abstract: With the growing global demand for clean energy, electrocatalytic water splitting has gained significant attention as a sustainable route for hydrogen production. Prussian blue analogs (PBAs) have emerged as promising materials due to their tunable composition, low cost, and environmental friendliness, positioning PBAs as viable alternatives to conventional Pt. Recent efforts have focused on high-entropy PBAs (HEPBA), which integrate multiple metal species into a single-phase lattice. This entropy-driven strategy induces lattice distortion and localized atomic strain, thereby optimizing the adsorption of water molecules and accelerating catalytic kinetics. However, the constant poor electrical conductivity limits their practical application, especially under alkaline conditions. To address this limitation, high-entropy transition metal phosphides were derived from HEPBA and compared to the bimetallic-derived analogues to unravel the role of configurational entropy. Our result revealed distinct lattice distortion in HEPBA relative to PBAs, consistent with entropy-driven structural disorder and local strain. Furthermore, XAS analysis demonstrated that the HEPBA-derived transition metal phosphides (HEPBA-TMP) exhibits shorter M–P bonds than conventional PBA-derived TMP, indicating stronger metal–phosphorus interactions and confirming the entropy-driven electronic modulation. This bond contraction increases the electrophilicity of Co centers in HEPBA-TMP, thereby facilitating *H2O adsorption and dissociation during the hydrogen evolution reaction (HER). As a result, the HEPBA-TMP catalyst not only delivers a remarkable HER performance, which achieves 100 mA cm-2 at a low overpotential of 198 mV in 1.0 M KOH, but also presents promising durability under the high current density of 0.5 A cm-2 for a continuous 48-hour period. This work revealed that HEPBA-TMP exhibited outperforming conventional bimetallic-derived one, highlighting its entropy-driven potential as a next-generation, cost-effective electrocatalyst for hydrogen production.