Investigation of sensing properties of sol–gel processed 4 at%Sb:SnO2/TiO2 thin films

Boratto, Miguel H. [UNESP]; Ramos, Roberto A. [UNESP]; Scalvi, Luis V. A. [UNESP]

Investigation of sensing properties of sol–gel processed 4 at%Sb:SnO2/TiO2 thin films

Arquivos

2-s2.0-85030846253.pdf (1.44 MB)

Data

2018-01-01

Autores

Boratto, Miguel H.

Ramos, Roberto A.

Scalvi, Luis V. A.

Tipo

Artigo

Direito de acesso

Acesso aberto

Resumo

In this work we investigate the gas and photo sensing properties of the antimony doped tin oxide and titanium oxide (4 at%Sb:SnO2/TiO2) nanocrystalline thin films deposited by sol–gel dip-coating. Photoconductivity measurements are carried out under solar light spectra irradiation at different powers. These results show a photo sensitivity of the films in a lateral junction due to interfacial defects. Gas sensitivity was studied at different pressures, and higher conductivity is presented at lower pressure compared to oxygen-rich atmosphere. It occurs due to absence of oxygen adsorption on the semiconductors surface. TiO2 films are also investigated concerning its properties to gas sensing under photo-excitation with InGaN LED light source with wavelength centered in 450 nm. The decay of photo-induced current evaluated under O2 and vacuum atmospheres shows that the sample illumination may contribute to higher gas-sensitivity. This measurement allows determining the charge carrier capture energy, that is related to trapping dominated by distinct defects in each atmosphere.