| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1544197 | Physica E: Low-dimensional Systems and Nanostructures | 2015 | 7 Pages |
Metal-oxide nanocomposites were prepared over screen-printed gold electrodes to be used as room-temperature NOx (nitric-oxide (NO) and nitrogen dioxide (NO2)) sensors. Various weight ratios of SnO2–WO3 and Pt loadings were used for NO sensing. The sensing materials were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and BET surface analysis. The NO-sensing results indicated that SnO2–WO3 (1:2) was more effective than other materials were. The sensor response (S=resistance of N2/resistance of NO=RN2/RNO) for detecting 1000 ppm of NO at room temperature was 2.6. The response time (T90) and recovery time (TR90) was 40 s and 86 s, respectively. By further loading with 0.5% Pt, the sensor response increased to 3.3. The response and recovery times of 0.5% Pt/SnO2–WO3 (1:2) were 40 s and 206 s, respectively. The linearity of the sensor response for a NO concentration range of 10–1000 ppm was 0.9729. A mechanism involving Pt promotion of the SnO2–WO3 heterojunction was proposed for NO adsorption, surface reaction, and adsorbed NO2 desorption.
Graphical abstractThe 0.5% Pt/SnO2–WO3 sensor responses increased from 1.2 to 3.3 when the gaseous NO concentrations were increased from 10 to 1000 ppm.Figure optionsDownload full-size imageDownload as PowerPoint slide
