Copper incorporated mesoporous materials: synthesis, characterization and catalytic activity in benzaldehyde reduction

Abstract

Copper substituted mesoporous silica materials (Cu–HMS-n), with a variety of Si/Cu atomic ratios (n) ranging from 50 to 100, were synthesized by the one-pot sol–gel method using dodecylamine as template. These materials were characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscopy, ultraviolet and visible diffuse reflectance spectroscopy, H2 temperature-programmed reduction, inductively coupled plasma-optical emission spectrometry, thermal analysis and X-ray photoelectron spectroscopy. All the samples showed worm-like mesoporous structures with surface areas higher than 700 m2 g−1 and pore volumes higher than 0.75 cm3 g−1. The catalytic activity of these materials in the reduction of benzaldehyde was evaluated. Effects of the Si/Cu atomic ratio in the catalyst and the influence of time and reaction temperature on the catalytic activity were investigated. Best catalytic performance was obtained with Cu–HMS-50 with a benzaldehyde conversion of 56% and a selectivity of 28% to benzyl alcohol.