Highly Dispersed Cobalt Phosphide in Zeolites: Unlocking Superior Efficiency in Ammonia Borane Hydrolysis

Abstract Ammonia borane (AB) is a promising material for chemical hydrogen storage; however, efficient hydrogen generation often relies on expensive noble metal catalysts. Herein, highly dispersed sub‐3 nm transition metal phosphide nanoparticles supported in amino‐functionalized Beta zeolites are developed using a facile impregnation method. The optimized Co‐Co ₂ P/NH ₂ ‐Beta catalyst, benefiting from the structural modulation of cobalt phosphides and their interaction with the Brønsted acid sites of zeolites, achieves a high hydrogen generation rate of 240.0 mol _H2 mol _Co ⁻¹ min ⁻¹ at 298 K during AB hydrolysis. Both experimental results and theoretical calculations emphasize that Co ₂ P exhibits stronger adsorption and lower dissociation energy barriers for both H ₂ O and AB compared to CoP. Furthermore, the introduction of metallic Co and/or phosphorus vacancies into Co ₂ P through H ₂ reduction significantly enhances catalytic efficiency. This work provides valuable insights for the design of high‐performance zeolite‐supported ultrasmall TMP catalysts, paving the way for more efficient chemical hydrogen storage solutions.