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.