科研之友
微信
新浪微博
Facebook
分享链接
摘要
In this work , the cataluminescence ( CTL) phenomenon of propylene oxide (PO) on the surface of nanocomposite TiO2-Y2O3 ( titanium dioxide-yttrium (III)-oxide ) was studied. It was found that the nanocomposite had high sensitivity and good selectivity for the detection of PO. The common volatile organic compounds such as acetone, acetaldehyde and benzene showed no response to the catalysis of TiO2 -Y2O3. Based on this phenomenon, a PO CTL sensor was designed. The ratio of TiO2 and Y2O3, and the sintering temperatures of the composites were optimized. It was found that when the mass ratio of TiO2 and Y2O3 was 1 :3 and the sintering temperature was 500 degrees C, the catalytic materials showed the best performance. The temperature, wavelength and carrier gas flow rate of the CTL system were also optimized , and 197 degrees C , 490 nm and 0. 3 L/min were selected as the optimal conditions. The quantitative analysis was performed under the optimized conditions and CTL intensity was linear with PO concentration in the range from 4. 5 mg/L to 1375 mg/L with a detection limit (3 sigma) of 1. 25 mg/L. The sensor was used for quantitative analysis and real-time monitoring of PO residues in fumigation cereals. The result obtained by this CTL sensor was consistent with that by gas chromatography. The CTL sensor proposed here had many merits such as high sensitivity, rapidity and simple operation, and had potential application prospects in the rapid detection of PO in food. In addition, the mechanism of catalytic oxidation of PO was discussed as well.
- 单位
