Dependences of Characteristics of Sensors Based on Tin Dioxide on the Hydrogen Concentration and Humidity of Gas Mixture

• Published in: Russian physics journal Vol. 60; no. 1; pp. 90 - 100
• Main Authors: Gaman, V. I., Almaev, A. V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-05-2017; Springer; Springer Nature B.V
• Subjects: Adsorption; Analysis; Charge density; Condensed Matter Physics; Economic impact; Hadrons; Heavy Ions; Humidity; Hydrogen; Hydroxides; Hydroxyl groups; Lasers; Mathematical and Computational Physics; Nuclear Physics; Optical Devices; Optics; Oxygen ions; Photonics; Physics; Physics and Astronomy; Physics of Semiconductors and Dielectrics; Sensors; Surface charge; Theoretical; Tin compounds; Tin dioxide; Tin oxides; kinetic equation; absolute humidity; adsorption centers; thermo-cyclic mode; energy band bending; tin dioxide; hydrogen; hydroxyl groups
• ISSN: 1064-8887; 1573-9228
• DOI: 10.1007/s11182-017-1046-2

An expression is obtained for the energy band bending eφ
sH
on the surface of the SnO
2
film in the clean air + hydrogen mixture. It is assumed that the value of eφ
sH
depends not only on the surface charge density of adsorbed oxygen ions O
¯
, but also on the negative charged hydroxyl groups (OH
¯
). The results of the analysis of the dependences of eφ
sH
on the hydrogen concentration
n
H
2
and the absolute humidity of the gas mixture obtained during the operation of the sensor in the thermo-cyclic mode are presented. A method for the determining
n
H
2
in the examined gas mixture is proposed. The method based on the dependence of eφ
sH
on the hydrogen concentration established during the calibration of the sensor is proposed. The dependences of the energy band bending on the SnO
2
surface at
n
H
2
= 0 and the conductivity of the sensor on its temperature during the heating period are discussed.