Hydrolysis of ammonia borane is deemed as a promising technique for robust hydrogen production, yet its deployment is still restricted due to the sluggish kinetics of the water dissociation step. An appropriate catalyst that can effectively reduce the H₂O dissociation barrier is quite desirable for sustainable ammonia borane-to-hydrogen conversion. Herein, an amino pre-coordination confinement strategy is profiled to achieve sub-2 nm ordered PtCo intermetallics uniformly on N-doped hollow mesoporous carbon spheres (O-PtCo/NHMS) for ammonia borane catalytic hydrolysis. Such a confined approach showcases the capacity of preventing nanoparticles from agglomeration and growth for accurate size control and can be extended to other ordered intermetallic systems (e.g. PtFe and PtCu). As for the ammonia borane hydrolysis, the ordered PtCo intermetallics have delivered a five times higher turnover frequency activity of 1264.1 min⁻¹ than that of the disordered PtCo catalyst, together with excellent catalytic durability. Mechanism studies indicate that the ordered PtCo structure promotes the balanced adsorption of H₂O and ammonia borane molecules at Co and Pt sites and reduces the energy barrier for the rate-determining H₂O dissociation step to boost the ammonia borane hydrolysis. This work provides valuable insights into the rational design of efficient ordered PtM intermetallic catalysts and expands their application in hydrogen production via ammonia borane hydrolysis.

The catalyst innovation that aims at noble-metal-free substitutes is one key aspect for future sustainable hydrogen energy deployment. In this paper, a nickel cobalt sulfoselenide/black phosphorus heterostructure (NiCoSe|S/BP) was fabricated to realize the highly active and durable water electrolysis through interface and valence dual-engineering. The NiCoSe|S/BP nanostructure was constructed by in-situ growing NiCo hydroxide nanosheet arrays on few-layer BP and subsequently one-step sulfoselenization by SeS₂. Besides the conductive merit of BP substrate, holes in p-type BP are capable of oxidizing the Co²⁺ to high-valence and electron-accepting Co³⁺, benefiting the oxygen evolution reaction (OER). Meanwhile, Ni³⁺/Ni²⁺ ratio in the heterostructure is reduced to maintain the electrical neutrality, which corresponds to the increased electron-donating character for boosting hydrogen evolution reaction (HER). As for HER and OER, the heterostructured NiCoSe|S/BP electrocatalyst exhibits small overpotentials of 172 and 285 mV at 10 mA cm⁻² (η₁₀) in alkaline media, respectively. And overall water splitting has been achieved at a low cell potential of 1.67 V at η₁₀ with high stability. Molecular sensing and density functional theory (DFT) calculations are further proposed for understanding the rate-determine steps and enhanced catalytic mechanism. The investigation presents a deep-seated perception for the electrocatalytic performance enhancement of BP-based heterostructure.