Palladium nanoparticles supported on mesoporous carbon nitride for efficiently selective oxidation of benzyl alcohol with molecular oxygen

Abstract

Ordered mesoporous carbon nitride (CN) has been synthesized through a nanocasting approach and utilized as a catalyst support to load Pd nanoparticles. The physical and chemical properties of Pd/CN materials were characterized using various techniques, including N2 adsorption–desorption, XRD, small-angle X-ray scattering, TEM, XPS, FT-IR, O2-TPD, and CO2-TPD. The ordered mesoporous structures of CN have well remained after the introduction of Pd nanoparticles. In selective oxidation of benzyl alcohol under mild aerobic condition, Pd/CN materials showed excellent and recyclable catalytic conversions of benzyl alcohol. Under the same reaction condition, the catalytic activity acquired over Pd/CN was superior to those obtained over Pd/CNTs, Pd/AC, and Pd/mpg-C3N4 catalysts. The characterization revealed that mesoporous CN support with basic nitrogen-containing sites could not only disperse well the Pd nanoparticles but also facilitate in activating alcohol molecules. Furthermore, in a tandem reaction combining selective oxidation and Knoevenagel condensation, Pd/CN material also showed potential catalysis with its bifunctionality.