Kinetics of gas response to reducing gases of SnO2 films, deposited by spray pyrolysis

Korotcenkov, Ghenadii; Brînzari, V.; Golovanov, V.; Blinov, Yu. F.

doi:10.1016/j.snb.2003.08.022

Cited by 101 publications

(54 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As mentioned above, the humidity controls the resistance behavior of the porous film at high temperature, which implies that hydroxyl groups may interfere with the adsorption of oxygen species. If it is true, it can be suggested that hydroxyl groups control the surface site occupation (39) and inhibit the reaction of H 2 with oxygen species, resulting in a low sensitivity of the porous film at high temperature. On the other hand, the dense film shows a high sensitivity at high temperature.…”

Section: Resultsmentioning

confidence: 99%

Structure and H2 Sensing Property of TiO2 Sputtered Films Deposited under Various Discharge Gas Pressures

Dan¹,

Yamazaki

Kikuta³

et al. 2012

Sensors and Materials

View full text Add to dashboard Cite

TiO 2 films were deposited by direct current (DC) magnetron sputtering under various discharge gas pressures. The structure of the films was investigated with focus on porosity, which was quantatitively evaluated on the basis of density and effective surface area. Furthermore, the H 2 sensing property of the films was investigated at different operating temperatures in ambient air. As-deposited films were amorphous. They crystallized to be of an anatase structure by annealing at 500°C. Films deposited under low pressure were smooth, whereas the films deposited under high pressure were composed of columnar grains. After annealing, the columnar grains were well defined, and the grain size increased with increasing annealing temperature. As the pressure during deposition increased, voids developed between columnar grains. The density decreased and the effective surface area increased with increasing pressure, indicating the formation of a porous film. A dense film deposited under low pressure showed sensitivity only at operating temperatures above 200°C. With decreasing density caused by increasing pressure, the sensing temperature decreased. The porous film annealed at 500°C showed a high sensitivity even at a low temperature of 100°C.

show abstract

Section: Resultsmentioning

confidence: 99%

Structure and H2 Sensing Property of TiO2 Sputtered Films Deposited under Various Discharge Gas Pressures

Dan¹,

Yamazaki

Kikuta³

et al. 2012

Sensors and Materials

View full text Add to dashboard Cite

show abstract

“…The hydroxyl groups and oxygen atoms are most likely to adsorb on the same centers, which can be, for example, the nonstoichiometric surface tin atoms. As the temperature Т increases from 523 to 723 K, the concentration of hydroxyl groups sharply decreases due to desorption [4]. Correspondingly, the concentration of oxygen adsorption centers increases.…”

Section: Conditions For Applicability Of Theory To Description Of Expmentioning

confidence: 98%

“…In the operating temperature range of hydrogen sensors (Т > 423-523 K), oxygen is adsorbed on the SnO 2 surface in the form of О -ions [1, 2,4]. The discontinuous platinum layer deposited on the SnO 2 surface facilitates dissociation of O 2 molecules into atoms.…”

Section: Conductivity Of First-type Sensors In Dry Airmentioning

confidence: 99%

See 1 more Smart Citation

Basic physics of semiconductor hydrogen sensors

Gaman

2008

Russ Phys J

View full text Add to dashboard Cite

The most probable physical models of hydrogen sensors based on thin stannic oxide films, MOS-structures, and tunnel MOS-diodes are discussed. The emphasis is on the mechanisms of formation of sensor response to hydrogen. The analytical equations describing the dependence of the response on the hydrogen concentration n Н 2 are derived for all types of sensors. The relations describing the dependences of the SnO 2 -sensor conductivity and response on the absolute humidity of a gas mixture are given. It is shown that the relaxation time τ rel of the response of SnO 2 -and MOS-structure sensors is determined by the relaxation time τ а of hydrogen atom adsorption on the SnO 2 and SiO 2 surfaces, respectively. For the MOS-diodes, τ rel = τ а at n Н 2 <3⋅10 3 ppm and τ rel = τ d at n Н 2 ≥ 7.5⋅10 3 ppm, where τ d is the relaxation time of hydrogen atom diffusion through an SiO 2 layer.

show abstract

“…R.f. sputtering [74], dc-magnetron sputtering [75], thermal evaporation [76,77], ion beam deposition [78], spray pyrolysis [79], and Sol-gel [80] are the most studied methods for the preparation of SnO 2 . Sberveglieri [81] presented a review of the techniques applied for SnO 2 films deposition and it was shown that most of the methods require high-temperature treatments in order to fabricate good-quality polycrystalline films.…”

Section: Nanocrystalline Metal Oxide-based Methane Sensorsmentioning

confidence: 99%

Nanocrystalline Metal Oxides for Methane Sensors: Role of Noble Metals

Basu

2009

Journal of Sensors

130

View full text Add to dashboard Cite

Methane is an important gas for domestic and industrial applications and its source is mainly coalmines. Since methane is extremely inflammable in the coalmine atmosphere, it is essential to develop a reliable and relatively inexpensive chemical gas sensor to detect this inflammable gas below its explosion amount in air. The metal oxides have been proved to be potential materials for the development of commercial gas sensors. The functional properties of the metal oxide-based gas sensors can be improved not only by tailoring the crystal size of metal oxides but also by incorporating the noble metal catalyst on nanocrystalline metal oxide matrix. It was observed that the surface modification of nanocrystalline metal oxide thin films by noble metal sensitizers and the use of a noble metal catalytic contact as electrode reduce the operating temperatures appreciably and improve the sensing properties. This review article concentrates on the nanocrystalline metal oxide methane sensors and the role of noble metals on the sensing properties.

show abstract

Kinetics of gas response to reducing gases of SnO2 films, deposited by spray pyrolysis

Cited by 101 publications

References 18 publications

Structure and H2 Sensing Property of TiO2 Sputtered Films Deposited under Various Discharge Gas Pressures

Structure and H2 Sensing Property of TiO2 Sputtered Films Deposited under Various Discharge Gas Pressures

Basic physics of semiconductor hydrogen sensors

Nanocrystalline Metal Oxides for Methane Sensors: Role of Noble Metals

Contact Info

Product

Resources

About