• P. N. Shelke
• D. V. Rasal
• P. L. Machale
• M. T. Sarode
• Y. B. Khollam

The Co3O4 films were deposited on thoroughly cleaned stainless steel, copper and glass substrates by using spray pyrolysis deposition technique from solution of cobalt sulphate (CoSO4:7H2O) and cobalt chloride (CoCl2:4H2O) in 1:1 of mixture of water and methanol. As-deposited films were heated at 350 oC/2 hr. The resultant films were characterized by using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy (SEM). The LPG and NH3 gas sensing properties of these films were measured at room temperature (RT) by using static gas sensing system at different concentrations (∼25 ppm to 350 ppm) of test gas. The XRD and Raman spectroscopy studies clearly indicated the formation of pure cubic spinel Co3O4 in all films. The LPG and NH3 gas sensing properties of films showed the increase in sensitivity factor (S.F.) with gas concentrations and more sensitivity to LPG as compared to NH3 gas. The maximum S.F. = 258 and 274 were found for NH3 and LPG gases respectively for the films deposited on glass substrate. For all films, the response time (2- 4 min.) is found to be higher than the recovery time (30 - 45 sec.). For all films, the response and recovery time are found to be higher for LPG as compared to NH3 gas. Further, repeatability - reproducibility in gas sensing properties was noted for all films.

Co3O4 films; Spray Pyrolysis deposition; Gas sensing; LPG; NH3; Sensitivity

"Spray pyrolysis deposited Co3O4 films for LPG and NH3 sensing", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 5, page no.96-101, May - 2019, Available :http://www.jetir.org/papers/JETIRCP06017.pdf

"Spray pyrolysis deposited Co3O4 films for LPG and NH3 sensing", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 5, page no. pp96-101, May - 2019, Available at : http://www.jetir.org/papers/JETIRCP06017.pdf