Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10410936 | Sensors and Actuators B: Chemical | 2005 | 6 Pages |
Abstract
α-Fe2O3 hydrosol was synthesized by sol-gel method with FeCl3·6H2O as the raw material and its thin films were prepared by dip-coating technique. The structure, morphology and spectroscopy of the thin films were characterized by XRD, AFM, UV-vis and FT-IR analysis methods. The results showed that uniform α-Fe2O3 monolayer and multilayers could be obtained at certain dip-coating speed. The particles were pseudocubic shaped, with the mean particle size of about 58 nm. The formation mechanism of α-Fe2O3 particles was explored by IR spectra and the change of the system acidity and conductivity. The results indicated that α-Fe2O3 particles formed from the intermediate complex β-FeOOH. The gas-sensing properties of the multilayers to alcohols with different chain length were measured at room temperature. The thin films exhibited high sensitivity and rapid response-recovery characteristics to these gases. The film can detect C3H7OH vapor concentration as low as 2 ppm. The response and recovery time of the film to CH3OH and C2H5OH vapor is within 20 and 50 s, respectively.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Lihua Huo, Qiang Li, Hui Zhao, Lijun Yu, Shan Gao, Jinggui Zhao,