Investigation of ZnO Thin Film Synthesized by Spray Pyrolysis Method as a Toxic Gases Sensor

• Published in: Journal of electronic materials Vol. 46; no. 10; pp. 5889 - 5894
• Main Author: Khojier, K.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-10-2017; Springer Nature B.V
• Subjects: Ammonia; Benzene; Carbon monoxide; Characterization and Evaluation of Materials; Chemical composition; Chemistry and Materials Science; Chlorine; Crystal structure; Crystallography; Electronics and Microelectronics; Emission analysis; Formaldehyde; Hydrogen sulfide; Instrumentation; Investigations; Materials Science; Nitrogen dioxide; Operating temperature; Optical and Electronic Materials; Photovoltaic cells; Reproducibility; Selectivity; Sensors; Solid State Physics; Spray pyrolysis; Thickness; Thin films; Toluene; Zinc oxide; ZnO; toxic gases; sensitivity; spray pyrolysis; Thin film
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-017-5583-9

In recent years, environmental pollution, particularly toxic gases and vapors, have greatly increased; hence, their detection has become increasingly important. This paper investigates ZnO thin films fabricated by the spray pyrolysis method to fabricate a toxic gases sensor. A ZnO thin film of 100 nm thickness was deposited on a glass substrate at 100°C. The crystallographic structure was characterized by x-ray diffraction and a field-emission scanning electron microscope was employed to investigate the surface physical morphology and chemical composition. Sensitivity and selectivity of the sample were tested with respect to different toxic gases and vapors including carbon monoxide, ammonia, hydrogen sulfide, chlorine, nitrogen dioxide, benzene, formaldehyde and toluene in the temperature range of 100–300°C. The results showed that the ZnO thin film is more selective to NO
2
gas than the other toxic gases and vapors in the studied temperature range. The ZnO thin film-based NO
2
gas sensor also showed a good reproducibility, stability, and detection limit of 10 ppm at the operating temperature of 200°C.