Spatially Compartmentalized Hydrocracking of Naphthalene over Core–Shell Ni/Y@mesoSiO ₂ Catalyst for Selective BTX Formation

A core–shell Y@mesoSiO2 (Y@MS) micro-mesoporous composites with tunable pore distribution and optimized acidity were synthesized via a facile aqueous–organic biphasic interfacial strategy, which was utilized as superior supports for spatially compartmentalized hydrocracking catalysts (Ni/Y@MS) of naphthalene. The radial divergent mesoporous channels in the silica shell promote uniform dispersion of Ni nanoparticles while mitigating reactant diffusion limitations, enabling spatial separation of catalytic reactions between the acidic Y zeolite core and SiO2 shell. Coating mesoporous silica on the Y zeolite surface not only regulates acid site distribution and suppresses carbon deposition but also enhances the structural stability of the Y zeolite framework during reactions. The ultrafine Ni nanoparticles can expose more active sites and enhance hydrogenation activity. Furthermore, a reaction pathway elucidating the synergistic catalysis mechanism involving the shape-selectivity of the Y zeolite core combined with the precracking functionality of the mesoporous SiO2 shell was proposed. The optimum Ni/Y@MS catalyst presented superior hydrocracking activity of 98.6%, the BTX yield of 69.3%, the kinetic constant of 2.0 h–1 and turnover frequency of 24.4 h–1 due to the synergistic interplay of the spatial confinement effect of the core–shell structure, suitable acidity and uniformly dispersed Ni0 species.