壓電石英傳感器測定空氣中氮氧化物

通過電化學(xué)活化和硅烷偶聯(lián)劑在石英諧振器的金電極表面修飾對氮氧化物(NOx) 敏感的金屬酞菁化合物,制成壓電氣體傳感器。探討了不同敏感材料對NOx 的響應(yīng)靈敏度、檢出限及載氣流速、溫度和干擾氣體等對傳感器的響應(yīng)和回復(fù)特性的影響。結(jié)果表明:酞菁鉛最敏感;其適宜的載氣流速為40 mLPmin ,溫度范圍為10～40 ℃;在9155 ×10 - 4～1191 mgPm3 質(zhì)量濃度范圍內(nèi),有良好的線性響應(yīng)關(guān)系;用于大氣中NOx的測定,有較好的可靠性和準(zhǔn)確性。使用壽命約300 次。
關(guān)鍵詞: 壓電石英傳感器(PQS) ; 氮氧化物(NOx) ; 響應(yīng)靈敏度; 檢出限

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