Propane dehydrogenation (PDH) is one of the most effective methods to produce propylene. But the industrial Pt‐based catalysts often suffer from short‐term stability under the high temperature reaction environment (500–700°C) via sintering and coke deposition. Herein, stable PDH reaction in high propylene yield has been achieved by the confinement of Pt–Zn intermetallic alloys (IMAs) in the channels of silicalite‐1. Single‐site Zn in the MFI framework was found to play a key role on assisting and stabilizing the PtZn IMAs for efficient PDH. By the cooperative action of the spatial confined PtZn IMAs and the lattice confined framework Zn, high propylene selectivity (>99%) without obvious deactivation was realized on the as‐developed catalyst (PtZn@S‐1) under 600°C even after 90 h. The low deactivation constant (0.003 h−1) was 6 times lower than that of the industrial PtSn catalyst.

Propane dehydrogenation (PDH) is one of the most promising techniques to produce propylene. Industrial Pt-based catalysts often suffer from short-time stability under high temperature due to serious sintering and coke deposition via undesired side reactions. Detailed reaction mechanism on the surface of Pt-based nanoparticle has been well studied, while the subsurface effect remains mostly unstudied. Herein, supported PtGa nanoparticles with different surface and subsurface composition was evidenced by extended X-ray absorption fine structure (EAXFS) spectra and energy dispersive X-ray spectroscopy (EDS). Theoretical simulation demonstrated subsurface regulation would increase the electron density of surface Pt and thus weaken propylene adsorption. Propylene selectivity on the PtGa-subsurface nanoparticles was up to 98% at 600 °C while that on the Pt-subsurface nanoparticles was only 95%. Furthermore, rational designed PtGa alloy nanoparticles were encapsulated in MFI zeolite to inhibit sintering and coke deposition for enhanced catalytic stability.

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