四对溴苯基铂卟啉聚氯乙烯敏感膜溶解氧传感器的研究

Platinum-tetra(4-Bromophenyl)porphyrin Polyvinyl Chloride Membrane Optical Dissolved Oxygen Sensor

介绍了四对溴苯基铂卟啉的合成及以它为敏感材料 ,以PVC粉为支持体系的光学溶解氧传感器的响应特性。该敏感膜的最大激发波长与发射波长分别为 4 0 2nm和 6 6 4nm ,并具有良好的稳定性、重现性 ;其对溶解氧的响应值I0 /I =1 5 ,其中I0 是敏感膜在 5 %亚硫酸钠溶液制备的无氧水中的荧光强度 ,I为其在空气饱和的水中的荧光强度。该敏感膜有较好的灵敏度 ,并用于实际水样的溶解氧测定 。

This paper describes the preparation of platinum-tetra (4-bromophenyl) porphyrin (PtTBPP) and the sensing characteristics of the dissolved oxygen photosensor with PtTBPP as sensing element and PVC as support system. The membrane works on the molecular oxygen quenching the fluorescence of the metalloporphyrin at the wavelength of 664 run when excited at the wavelength of 402 rim. It shows a very high sensitivity to dissolved oxygen with the ratio of I-0/I = 15 where I-0 is the fluorescence intensity in 5% Na2SO3 solution (deoxygenated water) and I is the fluorescence intensity in air saturated water. The membrane has good reversibility. Its response to repeat cycles of air saturated water and nitrogen saturated water is complete reversible. During the oxygen concentration range of 0 similar to 0.17 mL/m(3), the membrane's fluorescence intensity decreased by about 11% which demonstrates that it is very sensitive to trace oxygen in water. The photostability of the membrane is extremely good. There is no sign of photodegration when it is exposed to xeon lamp for 1 h in 5% Na2SO3 solution. The membrane has also been used to the analysis of water sample, its accuracy is satistactory compase with the Winkler method.