压电石英传感器测定空气中氮氧化物

通过电化学活化和硅烷偶联剂在石英谐振器的金电极表面修饰对氮氧化物(NOx) 敏感的金属酞菁化合物,制成压电气体传感器。探讨了不同敏感材料对NOx 的响应灵敏度、检出限及载气流速、温度和干扰气体等对传感器的响应和回复特性的影响。结果表明:酞菁铅最敏感;其适宜的载气流速为40 mLPmin ,温度范围为10～40 ℃;在9155 ×10 - 4～1191 mgPm3 质量浓度范围内,有良好的线性响应关系;用于大气中NOx的测定,有较好的可靠性和准确性。使用寿命约300 次。
关键词: 压电石英传感器(PQS) ; 氮氧化物(NOx) ; 响应灵敏度; 检出限

Abstract : The piezoelectric quartz sensor(PQS) was prepared by coating metal phthalocyanines(PcM) sensitive to nitrogen oxide(NOx) on the surface of Au electrode of quartz crystal resonator by electrochemical activation and silane coupling agent. The response sensitivities and detec2 tion limits of a variety of materials to NOx ,and effects of the flow velocity of carrier gas ,temperature and recovery characteristics of sensors were
investigated. The results indicated that lead phthalocyanine was the most sensitive to NOx ,that the appropriate flow velocity of carrier gas was 40 mLPmin and temperature range was 10～40 ℃,that the responses of sensor are fairly linear when the mass concentration is from 9155 ×10 - 4 to 1191 mgPm3 ,and that it has a good reliability and accuracy in the determination of NOx in the atmosphere. It could be used about 300 times.
Key words : piezoelectric quartz sensor(PQS) ; nitrogen oxide (NOx) ; response sensitivity ; detection limit