Electrochemical Materials Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, M.S., India.
Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea.
J Colloid Interface Sci. 2015 Aug 1;451:245-54. doi: 10.1016/j.jcis.2015.04.001. Epub 2015 Apr 7.
We report a study on effect of film thickness on NO2 sensing properties of sprayed WO3 thin films. WO3 thin films varying in thicknesses are deposited onto the glass substrates by simple spray pyrolysis technique by varying the volume of spray solution.Thin film gas sensors are characterized by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and photoluminescence (PL) techniques to study their physical properties. Film having thickness 745nm has shown highest gas response of 97% with 12 and 412s response and recovery times, respectively towards 100ppm NO2 concentration. Gas response of 20% is observed towards 10ppm NO2 at 200°C operating temperature. Sensitivity of the optimal sensor is 0.83%/ppm when operating at 200°C with 10ppm lower detection limit. The response of the sensor is reproducible and WO3 films are highly selective towards NO2 in presence of mist of various interfering gases viz. H2S, NH3, LPG, CO and SO2.
我们报告了一项关于喷雾 WO3 薄膜厚度对 NO2 传感性能影响的研究。通过简单的喷雾热解技术，通过改变喷雾溶液的体积，在玻璃基板上沉积厚度不同的 WO3 薄膜。通过 X 射线衍射（XRD）、X 射线光电子能谱（XPS）、扫描电子显微镜（SEM）、原子力显微镜（AFM）和光致发光（PL）技术对薄膜气体传感器进行了表征，以研究其物理性质。厚度为 745nm 的薄膜在 100ppm NO2 浓度下表现出最高的气体响应，分别为 97%，响应和恢复时间分别为 12 和 412s。在 200°C 的工作温度下，对 10ppm 的 NO2 观察到 20%的气体响应。在 200°C 下工作时，最佳传感器的灵敏度为 0.83%/ppm，检测下限为 10ppm。传感器的响应是可重复的，并且 WO3 薄膜在存在各种干扰气体（如 H2S、NH3、LPG、CO 和 SO2）的雾的情况下对 NO2 具有高度选择性。
