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

A core–shell Y@mesoSiO 2 (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 SiO 2 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 SiO 2 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 Ni 0 species.