Preparation of highly efficient bifunctional water electrolysis catalysts by controlling selenide d-band centers via polyatomic doping

Constructing MoSe 2 @Ni 3 Se 2 heterostructures optimized active site distribution and charge transport. • Three-dimensional nanostructure achieved high specific surface area and outstanding mechanical stability. • Synergistic Mn/Co/Se regulation optimizes adsorption behavior of reaction intermediates. • Theoretical calculations reveal d-p orbital hybridization as the electronic-scale mechanism for high activity. • Demonstrates highly efficient bifunctional full water splitting activity (1.57 V@10 mA cm −2 ). This paper reports an MCS-MoSe 2 @Ni 3 Se 2 /NF composite electrocatalyst with remarkable performance advantages, achieving breakthroughs in full hydrolysis performance through ingenious structural design and interfacial engineering. The catalyst first constructs MoSe 2 @Ni 3 Se 2 nanosheet arrays on a nickel foam substrate, followed by Mn–Co–Se introduction via electrodeposition for interfacial modification. This forms a unique spherical structure that substantially exposes active sites and optimizes electron transport pathways, significantly enhancing reaction kinetics. Under alkaline conditions, this material exhibits outstanding bifunctional catalytic activity: HER achieves 10 mA cm −2 at just 103 mV overpotential, while OER requires only 263 mV. Notably, when assembled as an integrated water electrolysis cell with simultaneous anode and cathode functions, it drives a current density of 10 mA cm −2 at a low voltage of 1.57 V and operates stably for over 50 h. Density functional theory calculations further reveal that its outstanding performance stems from the precise regulation of the material's d-orbital electronic structure by Mn–Co–Se. This creates a strong, broad d-p orbital hybridization region near the Fermi level, achieving an ideal balance between high conductivity and catalytic activity, thereby optimizing the reaction pathway. This work provides crucial material systems and theoretical insights for designing efficient, stable bifunctional water electrolysis catalysts. The MCS-MoSe 2 @Ni 3 Se 2 /NF structure engineered through interface design enhances water electrolysis performance by optimizing electron transfer pathways and regulating d orbitals. Download: Download high-res image (318KB) Download: Download full-size image