GS9.3 - Pd-coated SnO2 Nanorod Arrays for Detection of Dissolved H2 in Transformer Oil
- 17th International Meeting on Chemical Sensors - IMCS 2018
2018-07-15 - 2018-07-19
- Gas Sensors 9 - Hydrogen Sensing
- M. Kim, B. Jang, W. Lee - Department of Materials Science and Engineering, Yonsei University, Seoul (South Korea)
- 326 - 327
We report the enhanced sensing properties of the Pd-coated SnO2 nanorod (NR) arrays in detecting H2 gas in air and transformer oil. The Pd nanoparticles were coated on the SnO2 NR arrays, randomly ordered and vertically standing, by glancing angle deposition (GLAD) method which utilizes an electron-beam evaporator and DC magnetron sputtering system. The Pd-coated SnO2 NR arrays were optimized to have a high response (104 at 1 % H2) in air. The sensor materials were immersed and measured in the transformer oil that contains various concentration of dissolved H2. We found that the Pd-coated SnO2 NR arrays showed a superior performance in regard to the response (~96.3), the detection limit (0.3 ppm), and the response time (300 s). The Pd-coated SnO2 NR arrays had a temperature coefficient of resistance (TCR) of 3.69×10-3 °C-1 at various oil temperatures (20–80 °C). The sensing mechanism of the Pd-coated SnO2 NR arrays was also demonstrated by the decrease in the height of Schottky barrier at the interface of Pd/SnO2, upon exposure to H2. The excellent sensing performance in both air and oil are attributed to the synergistic effects originated from the high surface-to-volume ratio of NR arrays and the decreased Schottky barrier height of SnO2.