title: Preparation of porous chromium oxide nanotubes using carbon nanotubes as templates and their application as an ethanol sensor.
abstract: Chromium oxide nanotubes were successfully prepared using multi-walled carbon nanotubes (MWCNTs) as a template via a supercritical fluid-mediated route. In this method, with chromium (III) nitrate nonahydrate as precursor, chromium oxide was first deposited on MWCNTs in supercritical ethanol in the presence of NH(4)HCO(3). The as-prepared chromium oxide/MWCNT nanocomposites were characterized by transmission electron microscopy, x-ray diffraction, infrared spectroscopy and thermogravimetric analysis. It was demonstrated that the MWCNTs were coated with a layer of amorphous Cr(2)O(3)·xH(2)O. The thickness of the Cr(2)O(3)·xH(2)O sheath on MWCNTs could be tuned by manipulating the ratio of precursor to MWCNTs. Calcining the composites at 550 °C, the MWCNTs were removed, producing polycrystalline α-Cr(2)O(3) nanotubes. The as-prepared α-Cr(2)O(3) sample was used as a sensor material to detect ethanol vapor, and it was demonstrated that the α-Cr(2)O(3) nanotubes exhibited good performance even at 400 °C.
authors.affiliation: Beijing National Laboratory for Molecular Science (BNLMS), Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Science, Beijing 100080, People's Republic of China.
authors.forename: Guimin
authors.initials: G
authors.lastname: An
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Liu
authors.forename: Zhenjiang
authors.initials: Z
authors.lastname: Miao
authors.forename: Buxing
authors.initials: B
authors.lastname: Han
authors.forename: Shiding
authors.initials: S
authors.lastname: Miao
authors.forename: Jianping
authors.initials: J
authors.lastname: Li