Pt@Ni₂P/C₃N₄ for charge acceleration to promote hydrogen evolution from ammonia-borane

Incorporating g-C₃N₄ with transition metal phosphides is emerging as a low-cost and robust co-catalyst for hydrogen evolution. The ammonia borane hydrolysis is an efficient method to release H₂ at ambient conditions in the presence of a catalyst. An efficient and cheap catalyst is needed for practical application to achieve this benchmark. For this purpose, a catalyst Ni₂P/C₃N₄ is synthesized by hydrothermal method and low-temperature phosphidation. The optimization reveals that the Ni₂P/C₃N₄ with 6.5% Ni contents shows the best performance for H₂ release. Furthermore, 2% Pt nanoparticles loading over Ni₂P/C₃N₄ boosts the charge transfer and improves activity 5.7-fold compared to Ni₂P/C₃N₄, and the Pt-loaded catalyst is depicted as Pt@Ni₂P/C₃N₄. The reaction kinetics reveals that the hydrogen evolution rate accelerates by increasing the amount of Pt@Ni₂P/C₃N₄ and AB concentration, and the loading of Pt nanoparticles loaded over Ni₂P/C₃N₄ reduces the activation energy significantly. Moreover, the ionic interaction between Pt and Ni₂P/C₃N₄ generates Ptᵟ⁺ and (Ni₂P/C₃N₄)ᵟ⁻ active sites which facilitates B–H cleavage and O–H bonds of ammonia borane and water, respectively. Incorporating transition metals phosphide and noble metals supported over g-C₃N₄ paves the pathway toward the efficient H₂ evolution from ammonia borane, bringing cost-effective modifications to synthesize constructive catalysts.