We report on our systematic investigation of Au nanoparticles highly dispersed in the mesopores of (s)-(-)-2-pyrrolidinone-5-carboxylic acid (Py)-modified SBA-15 (Au/SBA-15-Py) by using a series of modern techniques. 13C NMR and IR spectroscopies indicate that Py species are successfully grafted on the surface of mesopores in SBA-15; XRD patterns and N2 adsorption isotherms show that the sample mesostructures are well preserved; TEM images clearly confirm the uniform Au nanoparticles in the mesopores; and XPS suggests an interaction between Au nanoparticles with Py species. Interestingly, Au/SBA-15-Py catalysts always exhibit superior catalytic properties in the oxidation of cyclohexene and styrene by molecular oxygen at atmospheric pressure, compared with the pyrrolidone-free SBA-15 supported Au catalyst (Au/SBA-15-N). This phenomenon is reasonably related to the interaction between Au nanoparticles with Py species, which is consistent with results analyzed from our density-functional theory (DFT) calculations.
Bibliographical noteFunding Information:
This work is supported by the National Natural Science Foundation of China (20973079) and the State Basic Research Project of China (2009CB623501). Dr. H. Wang was supported in part by the (USA) National Science Foundation (DMR-0903225) and by the Advanced Energy Initiative of West Virginia University. P. Hapala was supported by the Czech Republic Grant No. SVV-2010-263303.
- Au nanoparticles
- Cyclohexene and styrene oxidation by molecular oxygen