Propane dehydrogenation (PDH) is a key process for propylene production, but conventional catalysts are often constrained by high cost, environmental impact, and limited stability under harsh reaction conditions. Fe-based catalysts offer a cost-effective and sustainable alternative due to their intrinsic ability to activate C-H bonds in alkanes. However, precise control over the oxidation state and coordination environment of Fe species to balance PDH activity and stability remains challenging. Herein, we develop a molten-salt-assisted synthesis strategy integrated with CeO2-x-mediated interfacial engineering to finely tune the structural and electronic properties of Fe species supported on Al2O3. The molten salt medium enables uniform dispersion and controlled crystallization of Fe3O4, effectively mitigating its over-reduction during high-temperature H2 treatment. The subsequent incorporation of CeO2-x modulates the local electronic structure of Fe3O4, inducing a controlled partial reduction to metallic Fe0 and forming a well-defined Fe0-Fe3O4 dual-interface architecture. This interfacial electronic reconstruction enriches the electron density of low-valent Fe sites, facilitating efficient charge transfer during propane activation and promoting rapid propylene desorption. As a result, the optimized catalyst demonstrates accelerated PDH kinetics, high propylene selectivity, and enhanced resistance to coking. This work establishes a scalable route for constructing dual-interface active sites, providing a general design principle for low-cost, high-performance PDH catalysts.
Zhu et al. (Wed,) studied this question.