Bismuth-containing MCM-41: synthesis, characterization, and catalytic behavior in liquid-phase oxidation of cyclohexane

Bismuth-containing MCM-41 was directly synthesized in strongly acidic media with CPBr as the template. It was shown, for the first time, by ICP, XRD, N2 adsorption/desorption, TEM, SEM, 29Si MAS NMR spectra, UV-vis DRS, and Raman spectroscopy that all of the samples have high surface area and good crystallinity, and all bismuth atoms in Bi-MCM-41 are highly dispersed in the silica-based structure. In addition, XPS spectroscopic data indicate that most of the bismuth enters the internal surface or framework of MCM-41. In the catalytic test, Bi-MCM-41 was found to be a very efficient catalyst for the oxidation of cyclohexane, with oxygen as oxidant, in a solvent-free system, and it behaves truly as a heterogeneous catalyst.