Development of porphyrin dispersed sol-gel films as HCl sensitive optochemical gas sensor
Development of porphyrin dispersed sol-gel films as HCl sensitive optochemical gas sensor
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DOI：
10.1016/j.snb.2005.11.039
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发表时间：
2006-09-12
影响因子：
8.4
通讯作者：
Sadaoka, Yoshihiko
中科院分区：
文献类型：
--
作者：
Itagaki, Yoshiteru;Deki, Katsuyuki;Sadaoka, Yoshihiko
采用不同摩尔比的甲基三乙氧基硅烷(MTEOS)与四乙氧基硅烷(TEOS)、M/T(=4、8、16和32)制备卟啉分散的溶胶-凝胶复合薄膜，并利用光反射光谱技术对氯化氢(HCl)气体(0.5-5.0ppm)进行光化学检测。薄膜的光谱显示出在 419.3 nm（M/T = 4-16）和 418.3 nm（M/T = 32）的 lambda(m) 处的强索雷带。在索雷带测量的传感器的灵敏度强烈依赖于溶胶-凝胶薄膜的 M/T 比，到 0.5ppm 时，它导致 M/T=8 > 4 的顺序近似为 16 > 32。 从热重(TG)分析发现，M/T=4主要含有大量的水吸附。预测M/T=8时HCl的吸附能力最高，表现出最高的灵敏度。然而，在高浓度 HCl (>= 2.8 ppm) 下，M/T = 4 表现出与 M/T = 8 相当的灵敏度，这可能是由于 M/T = 4 具有大量的水吸附特性。尽管对 HCl 气体具有高灵敏度，但 M/T = 8 传感器对 0.5 ppm SO2 暴露几乎无声。 (c) 2005 Elsevier B.V. 保留所有权利。
The porphyrin dispersed sol-gel composite films were prepared from the different molar ratios of methyltriethoxysilane (MTEOS) to tetraethoxysilane (TEOS), M/T (=4, 8, 16 and 32), and optochemical detection of hydrogen chloride (HCl) gas (0.5-5.0ppm) was examined by using the photo-reflection spectral technique. The optical spectra of the films showed an intense Soret-band at lambda(m) of 419.3 nm for M/T = 4-16 and 418.3 nm for M/T = 32. The sensitivity of the sensors measured at the Soret-band strongly depended on the M/T ratio of the sol-gel films and to 0.5ppm it resulted in the order of M/T=8 > 4 approximate to 16 > 32. From the thermogravimetric (TG) analysis, it was found that M/T=4 contained a predominantly large amount of water adsorption. It is predicted that M/T = 8 has the highest adsorption capacity of HCl to exhibit the highest sensitivity. However, at high concentration of HCl (>= 2.8 ppm) M/T = 4 exhibited a comparable sensitivity to M/T = 8 probably due to the large amount of water adsorption property of M/T = 4. In spite of the high sensitivity to HCl gas, the M/T = 8 sensor was almost silent to the 0.5 ppm SO2 exposure. (c) 2005 Elsevier B.V. All rights reserved.