AACVD Grown WO3 Nanoneedles Decorated With Ag/Ag2O Nanoparticles for Oxygen Measurement in a Humid Environment

• Published in: IEEE sensors journal 2019-02, Vol.19 (3), p.826-832
• Main Authors: Sari, Wangi P., Blackman, Chris, Zhu, Yiyun, Covington, James A.
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Chemical sensor; Chemical sensors; Chemical vapor deposition; Decoration; Gas detectors; Gas sensors; heterojunction; Nanoparticles; Organic chemistry; oxygen detection; Oxygen probes; Relative humidity; Sensor arrays; Sensors; Silver; silver oxide; Substrates; Temperature measurement; Temperature sensors; thin film sensor; tungsten oxide; Tungsten oxides
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2018.2878051

A sensitive material consisting of silver/silver oxide decorated WO 3 was successfully grown in two steps via aerosol-assisted chemical vapor deposition. Morphological, structural, and composition analysis revealed that our method is effective for growing WO 3 nanoneedles decorated with silver/silver oxide nanoparticles at relatively low temperature (≤375 °C) onto sensor arrays printed on an alumina substrate. The sensors were tested for oxygen under humid environment (relative humidity ~85%) with the concentration ranging between 0% and 20%. Gas sensing results showed a good response to oxygen with optimum temperature which was observed at 400 °C for undecorated WO 3 and at 350 °C for silver/silver oxide decorated WO 3 . The addition of silver/silver oxide was found to improve the sensor response by almost 300%, making the sensor a potential alternative to replace an existing Pb-based oxygen sensor.