Elucidating interfacial active sites in ruthenium–boron nitride nanotube catalysts for efficient low-temperature ammonia-to-hydrogen conversion

Tailoring the interaction between metal nanoparticles and catalyst support presents a prominent strategy to enhance both the activity and durability in hydrogen (H₂) production catalysts. In this work, ruthenium nanoparticles (NPs) supported on boron nitride nanotubes (Ru/BNNT) are introduced as efficient and thermally robust catalysts for low-temperature ammonia (NH₃) decomposition. The unique curvature and ionic nature of BNNTs enable uniform Ru dispersion and metal-support interactions (MSIs), resulting in exceptional H₂ generation efficiency and long-term operational stability. In-situ transmission electron microscopy (TEM) reveals remarkable thermal resistance of Ru/BNNT with minimal nanoparticle sintering, while density functional theory (DFT) calculations uncover a dual-site mechanism in which interfacial Ru atoms promote NH₃ dissociation and adjacent Ru sites facilitate 2H* recombination and H₂ desorption. This cooperative interaction between metal NPs and the BNNT support underpins the outstanding catalytic performance and durability observed. The findings highlight the strategic potential of BNNTs as versatile supports for high-performance and stable catalysts in sustainable H₂ energy conversion and related catalytic processes.