点击次数：

论文类型：期刊论文

发表时间：2013-06-07

发表刊物：NANOSCALE

收录刊物：SCIE、EI、PubMed、Scopus

卷号：5

期号：11

页面范围：4823-4828

ISSN号：2040-3364

摘要：We report the preparation of ultrasmall monodisperse MoO3/SiO2 nanocomposites in reverse microemulsions formed by Brij-58/cyclohexane/water. The nanocomposites are of "raisin-bun"-type with 1.0 +/- 0.2 nm MoO3 homogeneously dispersed in 23 +/- 2 nm silica spheres. Characterization is carried out based on transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectrometry (EDS), X-ray powder diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-optical emission spectrometry (ICP-OES), N-2 sorption measurement, and NH3 temperature-programmed desorption (NH3-TPD). The as-prepared MoO3/SiO2 nanocomposites are microporous and exhibit enhanced catalytic activities for acetalization of benzaldehyde with ethylene glycol and can be repeatedly used 5 times without obvious deactivation. The catalytic performance improvement is attributed to the unique structure and ultrasmall size of the nanocomposites.