Optical sensors for dissolved sulfur dioxide
Optical sensors for dissolved sulfur dioxide
复制标题
溶解二氧化硫光学传感器
DOI：
10.1007/s002160051037
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
O. Wolfbeis
中科院分区：
文献类型：
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作者：
A. Stangelmayer;I. Klimant;O. Wolfbeis
摘要 开发并表征了用于测定二氧化硫的比色传感膜。这些薄膜可用于检测气相和水溶液中的痕量二氧化硫。亲脂性 pH 指示剂离子对固定在疏水性透气有机硅和苯基取代的有机硅中。暴露于 SO2 中时，薄膜会发生肉眼可察觉的颜色变化，从蓝色变为黄色。未观察到对 pH 值和 CO2 的交叉敏感性。响应时间取决于传感膜的厚度、膜中指示剂的浓度以及相应的 SO2 浓度。开发了响应时间 < 1 分钟 (t90) 的膜。对二氧化硫的敏感性取决于指示剂的 pKa。 pKa 增加会导致检测限降低。新型光学 SO2 传感器具有化学和机械稳定性，并且易于制造。如果避光保存，膜的保存稳定性至少为 7 个月。
Abstract Colorimetric sensing membranes for the determination of sulfur dioxide were developed and characterized. These films can be used for sensing trace amounts of sulfur dioxide both in the gas phase and in aqueous solutions. Lipophilic pH indicator ion pairs were immobilized in hydrophobic gas-permeable silicone and phenyl substituted ormosil. On exposure to SO2 the films undergo a visually detectable color change from blue to yellow. No cross-sensitivity to pH and CO2 was observed. Response times depend on the thickness of the sensing membranes, the indicator concentration in the film as well as on the respective SO2 concentration. Membranes with response times of < 1 min (t90) were developed. The sensitivity to sulfur dioxide depends on the pKa of the indicator. An increase in the pKa results in a lower detection limit. The new optical SO2 sensors are chemically and mechanically stable and are easy to manufacture. The storage stability of the membranes is at least 7 months if stored in the dark.