Enhanced ammonia gas sensing by cost-effective SnO2 gas sensor: Influence of effective Mo doping

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2023-12, Vol.298, p.116849, Article 116849
• Main Authors: Gayathri, K., Ravichandran, K., Sridharan, M., Suvathi, S., Sriram, S., Mohan, R., Jansi Santhosam, A., Praseetha, P.K., Sakthivel, P.
• Format: Article
• Language: English
• Subjects: Ammonia gas sensing; Cost-effective nebulizer spray pyrolysis; Molybdenum; SnO2
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2023.116849

•Preparation of cost- effective SnO2:Mo film sensor for NH3 sensing for the first time.•Remarkable response and recovery times are observed.•Tunable surface morphology and roughness by Mo doping.•Creation of sensing favourable oxygen vacancy. Metal oxide based semiconductors play a vital role in the development of cost-effective gas sensors. In this study, undoped and Mo-doped SnO2 films were deposited using nebulizer spray by varying Mo doping concentrations from 0 to 1.5 wt% (in steps of 0.5 wt%) at the substrate temperature of 350°C. Ammonia vapour was used as the test gas. The effect of Mo doping concentration on the gas sensing ability of SnO2 films was investigated. Among the tested samples, the SnO2: Mo film with 1 wt% of Mo doping exhibits the best response (21 s) and recovery (31 s) times. The XRD results revealed the tetragonal structure and a decrease in the crystallite size upon doping. The Mo doping caused noticable changes in oxygen vacancies (as observed from PL), surface morphology, grain size and surface roughness which are found to be favourable for effective gas sensing.