Embedding Monodisperse LaO_x Into Pt Nanoclusters for Ultra-Stable and Efficient Hydrogen Isotope Oxidation

Catalytic oxidation plays a crucial role in the efficient treatment of hydrogen isotopes, with the key technical challenge being the development of high-performance catalysts to enhance isotope removal efficiency, thereby reducing environmental pollution and ensuring public radiation safety. Herein, the strategic control of platinum nanoclusters confined within silicalite-1 zeolites is reported to enhance the high removal efficiency for hydrogen isotopes under low-temperature conditions for the first time. Incorporating a single lanthanum oxide (LaO_x) into Pt nanoclusters adapts the local charge of adjacent Pt atoms, significantly altering their electronic structure. The existence of individual LaO_x species is confirmed by X-ray absorption spectroscopy and aberration-corrected electron microscopy, and the performance enhancement mechanism is further probed by theoretical calculations. This embedded single LaO_x both facilitates local charge adjustment and supplies abundant active oxygen species, leading to performance enhancement by reducing the energy barrier of rate-determining step (O^* + H → OH^*), in accordance with the Mars-van Krevelen mechanism. Consequently, during a surprisingly long-term restart performance test (≈267 d), the PtLaOx@S-1 maintained a high conversion rate over 99% at 50 °C and a space velocity of 48,000 mL·g^-1·h^-1. This study highlights the potential of individual LaO_x sites for enhancing hydrogen isotope oxidation.