The nature of surface behavior of tin oxide doped sensors: X-ray photoelectron spectroscopy studies before and after exposure to liquid petroleum gas

✍ Scribed by A.R. Phani; S. Manorama; V.J. Rao

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 243 KB
• Volume: 61
• Category: Article
• ISSN: 0022-3697
• DOI: 10.1016/s0022-3697(99)00215-2

✦ Synopsis

X-ray photoelectron spectroscopy studies have been carried out to investigate the possible chemical species involved in the gas-solid interaction and enhancing mechanism of the Pd-doped SnO 2 sensor element. In the case of SnO 2 and SnO 2 /Al 2 Si 2 O 7 , when the samples are exposed to liquid petroleum gas (LPG), the SnO 2 is reduced to metallic Sn indicating adsorptiondesorption (chemical mechanism). Whereas in the case of SnO 2 /Pd and SnO 2 /Al 2 Si 2 O 7 /Pd systems in addition to chemical mechanism, there is an additional contribution from the Pd, in which PdO 2 and PdO are reduced to PdO and Pd, respectively, attributed to electronic mechanism. It has been observed that the electronic mechanism is more predominant than the chemical one.