Deposition of N-doped carbon layers inside acidic ZrSBA-15: significant enhancement of catalytic performance of Pd NPs toward benzyl alcohol aerobic oxidation

Palladium-based catalysts with equably distributions of surface functionalities are synthesized by anchoring palladium nanoparticles onto N-doped carbon layers stabilized by mildly acidic platelet ZrSBA-15 framework with short mesochannels. The catalysts were fully characterized by X-ray diffraction, N 2 adsorption-desorption isotherms, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Simultaneously, the Pd–NC–ZS catalysts exhibited the expectable activity in aerobic oxidation of benzyl alcohol with 82% conversion and absolute selectivity to benzaldehyde. Inappreciable loss in catalytic performance under solvent- and base-free conditions after ten times recycle demonstrated that there was strong interaction between palladium nanoparticles and the modified framework. Namely, a synergistic effect can be certified due to the surface acidic sites of ZrSBA-15 and N-doped carbon layers, which could strengthen the interaction between palladium nanoparticles and support, thus facilitating the anchoring and stabilization of palladium nanoparticles onto the pore walls of the NC–ZS. Graphical Abstract