Preparation of ruthenium-loaded CNT–TiO2 nanohybrids and their catalytic performance for the selective oxidation of benzyl alcohol

CNT–TiO2 nanohybrids were synthesized using CNTs as a substrate and isopropyl titanate as a titanium source by a hydrothermal method. The nanohybrids were characterized by SEM and XRD, and their dispersion ability as an emulsion was investigated by optical microscopy. Ruthenium was loaded onto TiO2 and the nanohybrids by an impregnation method, and their catalytic performance was evaluated by the selective oxidation of benzyl alcohol to benzylaldehyde. The mechanism involved in the reaction was proposed. Results show that the dispersion ability of the CNT–TiO2 nanohybrids, judged by the numbers of uniform oil droplets in water per unit liquid volume, is better than that of TiO2. The catalytic activity and selectivity of the Ru/CNT–TiO2 for the selective oxidation reactions are higher than for Ru/TiO2, indicating that they are closely related to the dispersion ability of the catalysts as emulsions.