硬脂酸复合薄膜光波导元件的气敏性研究

Gas Sensitivity Study of Stearic Acid Composite Film Optical Waveguide Sensor Element

利用旋转-甩涂法将聚乙烯吡咯烷酮(PVP)-硬脂酸复合薄膜固定在钾离子(K+)交换玻璃光波导表面,研制了PVP-硬脂酸复合薄膜/K+交换玻璃光波导元件,用于对挥发性有机物蒸汽进行检测。实验结果表明,在室温下该元件对低浓度的二甲苯蒸汽仍有较好的重复性和选择性响应,能够检测到1×10-6(体积分数)的二甲苯,其响应和恢复时间分别为9 s和35 s,相对标准偏差为±4.17%。该元件具有灵敏度高、响应-恢复速度快、可逆性好、成本低、容易制作等特点。

The polyvinyl pyrrolidone（PVP）doped stearic acid composite film was deposited onto the surface of a single mode potassium ion（K＋）exchanged glass optical waveguide OWG by spin coated method,the OWG sensor was fixed on the gas sensor system to detect VOCs gases.Experimental results showed that,the sensor has high repeatability and selectivity towards lower concentration xylene gas at room temperature,its response time and recovery time was 9 s and 35 s for 1×10-6 volume fraction xylene gas,the relative standard deviation（R.S.D）of output light intensity was ±4.17% at this concentration.The sensor is easily fabricated and had many advantages such as high sensitivity,fast response and recovery speed,good reversibility,low cost.