Tin oxide gas sensor on tin oxide microheater for methane sensing
Client: K. N. Toosi University of Technology
Date: 2015- Ongoing
Director project: Prof. Faramarz Hossein-Babaei
Project type: Pilot plant implementation
Project collaborator: Mohsen Gharesi, Maryam Moalaghi
Summary of project:
The explosive nature of methane and its role in global warming have made detecting its leakage important. Significant amounts of natural gas are lost along pipelines causing billion-dollar economic losses each year. The common chemiresistive methane sensors fail to satisfy the quality requirements for long-term operation in harsh environs. Particularly, the RuO2 microheaters utilized in these sensors deteriorate in reducing atmospheres and cannot provide the high temperatures required for methane detection in long term. In this project, a tin oxide gas sensor is fabricated on a tin oxide microheater which can stably operate at temperatures as high as 850 °C. Both components are produced by ultrasonic spray pyrolysis of tin chloride solutions on alternative sides of an alumina chip. Thermally stable electrical contacts are formed by diffusion bonding of gold wire segments. The device can detect 50 ppm of methane in normal atmosphere with a response time of 10 s.