Sensor Photoresponse of Thin-Film Oxides of Zinc and Titanium to Oxygen Gas

Abstract

Response of steady-state photoconductivity to changes in oxygen partial pressure (10 Ϫ3 to 1 atm) has been quantitatively studied in thin-film polycrystalline TiO 2 :Nb and ZnO at 80-120ЊC. The magnitude of photoconductivity varied as a square root of illumination intensity regardless of oxygen pressure. Both materials showed fast response to oxygen, although in different pressure ranges. Zinc oxide was more sensitive to lower oxygen pressures while titanium dioxide worked better at pressures close to 1 atm.

Morphology Control of Metal Oxide Nanocrystals

“…Deposition of ZnO whiskers having high aspect ratio on the substrate would provide a ZnO network film having a high specific surface area. These whisker films can be applied to gas sensors 23,24 or solar cells 25 …”

The influence of resistance and carrier concentration on the output voltage of a ZnO nanogenerator

“…The research has led to the development of numerous ZnO thin film and nanowire based devices ranging from surface acoustic wave filters [1], photonic crystals [2], light emitting diodes [3], photodetectros [4], photodiodes [5], gas sensors [6] and solar cells [7], to name a few. This is due to the unique properties of ZnO including a wide bandgap (3.37 eV) as well as specific electrical and optoelectrical properties of the II-VI semiconductor group [2][3][4].…”

Preparation of vertically aligned ZnO crystal rods in aqueous solution at external electric field

“…Zinc oxide is known to have a wide direct band gap of 3.37 eV [1] and large exciton binding energy of 60 meV at room temperature [2]. This oxide material could be applied in many devices such as light-emitting devices [3,4], transparent conducting layer for solar cells [5], field effect transistors [6] and gas sensors [7]. Among onedimensional (1D) structures such as nanorods, ZnO has the most interesting properties due to quantum confinement effect in reduced dimension.…”