Engineering bifunctional active sites in platelet-like hierarchical catalysts for enhanced hydrogen storage in naphthalene

• Platelet-like hierarchical catalysts with tunable acidity and active metal sites were synthesized. • The superior pore structure enhances the diffusion of naphthalene and the dispersion of active components. • The introduction of ZSM-5 seeds introduces abundant acidic sites to PZS composites. • The suitable acidity facilitates the formation of electron-deficient Pt δ+ species. • Pt/PZS-3 catalyst demonstrates exceptional naphthalene hydrogenation activity and decalin yield. Platelet-like ZSM-5/SBA-15 (PZS) micro-mesoporous composites featuring a two-dimensional hexagonal structure were prepared by nano-assembly method. Then hierarchical Pt/PZS catalysts with tunable acidity and active metal sites were synthesized. The superior pore structure of Pt/PZS catalysts enhances the diffusion of naphthalene and the dispersion of active components. The suitable acidity facilitates naphthalene adsorption, hydrogen spillover, and the formation of electron-deficient Pt δ+ species. Among the Pt/PZS catalysts designed, the catalyst with a SiO 2 /Al 2 O 3 molar ratio of 120 (Pt/PZS-3) exhibited exceptional naphthalene hydrogenation activity and hydrogen storage performance, achieving 100 % conversion rate of naphthalene and 100 % selectivity of decalin. The superior naphthalene hydrogenation activity and decalin yield of Pt/PZS-3 can be attributed to the synergistic effects of its superior textural properties, suitable acidity, and highly dispersed Pt particles. Additionally, the possible reaction mechanism for the hydrogenation of naphthalene to decalin was further investigated and proposed using the Pt/PZS catalyst system.