Investigation of Rapid Gas-Sensitive Properties Degradation of ZnO-Sn[O.sub.2] Thin Films Grown on the Glass Substrate

• Published in: Chemosensors 2020-06, Vol.8 (2), p.1
• Main Authors: Petrov, Victor V, Bayan, Ekaterina M, Khubezhov, Soslan A, Varzarev, Yuri N, Volkova, Maria G
• Format: Article
• Language: English
• Subjects: Chemical properties; Identification and classification; Thin films; Tin compounds; Zinc oxide
• ISSN: 2227-9040
• DOI: 10.3390/chemosensors8020040

ZnO-Sn[O.sub.2] films with a thickness of up to 120 nm have been prepared on glass substrates by pyrolysis at 550 [degrees]C of three spin-coated organic precursors films. Films of four compositions were obtained on glass substrates. The prepared films were characterized by SEM, XRD, and XPS analysis. Electrophysical studies have shown that the activation energy of the temperature conductivity for all films is equal to 0.75 eV. While the gas-sensitive characteristics by CO treatment in low concentrations at a temperature of 200-300 [degrees]C was studied, their rapid degradation was found. Studies using the XPS method have shown that ZnO-Sn[O.sub.2] films contain sodium, which is diffused from the soda-lime glass substrate during the film formation. Studies of XPS spectra after CO treatment have shown that the film surface is almost 50% composed of adsorbed water molecules and OH groups. OH groups are part of the sodium, tin, and zinc hydroxides formed on the surface. In addition, zinc hydrocarbonates are formed on the surface of the films. The detected insoluble compounds lead to the degradation of gas-sensitive properties of ZnO-Sn[O.sub.2] films.