Boron-interstitial Catalysts as Cathode and Anode Materials for Efficient Water Splitting

The growing demand for sustainable hydrogen production has driven extensive research on efficient and durable electrocatalysts for water electrolysis. Interstitial alloys incorporating boron (B) atoms within metallic lattices provide a versatile strategy to modulate geometric and electronic structures simultaneously. The incorporation of B induces lattice strain and alters the d-band position, thereby optimizing intermediate adsorption energies and enhancing both catalytic activity and durability. This review outlines the geometric stability principles of interstitial alloys and summarizes how boron interstitial incorporation governs structure–property relationships in the hydrogen and oxygen evolution reactions. The interplay between interstitial site occupancy, lattice distortion, and electronic coupling is highlighted as the key factor underlying performance improvement. The article concludes with perspectives on operando characterization and data-driven design approaches, establishing boron interstitial alloys as a promising platform for scalable, cost-effective, and durable catalysts in green hydrogen production.