Gas sensing properties of nano-crystalline SnO2-CuO compounds

We fabricated a micro gas sensor for hydrogen sulfide (H 2 S) gas using MEMS technology and the sol-gel process, and synthesized SnO 2 -CuO as a sensing material by the sol-gel method. Synthesized particles of SnO 2 -CuO were characterized with an average particle size of about 40 nm as measured by FE-SEM imagery and XRD peaks. The sensing material was coated on the micro platform and annealed at 400 °C. The maximum gas sensitivity (R s = R g /R a ) was 0.005 at 300 °C for 1.0 ppm — H 2 S. The gas sensitivity showed linear behavior with increasing H 2 S concentration.