Low Temperature Gas Sensing Coatings Made Through Wet Chemical Deposition of Niobium Doped Titanium Oxide Colloid

Naji Al Dahoudi

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DOI: 10.4236/msa.2011.24034                

Abstract

Niobium doped titanium oxide (TiO₂) colloid was synthesized to fabricate a hydrogen gas sensor layer on oxidized silicon wafer substrate. The layers were obtained using spin coating technique and then heated in air at 500°C for 30 min. The doping of TiO₂ led to a significant enhancement of the sensitivity of the layer especially at low operating temperature. The effect of doping was found effective of operating the sensor at relatively low temperature (150°C). The layers show a very smooth nanostructure with average roughness of less than 0.5 nm. The behavior of the sensing characteristics of such layers was discussed related to their chemical compositions, morphology and their crystalline structure. The morphological and structural characteristics of the layers were studied through X-ray diffraction (XRD) and Atomic force microscopy (AFM).

Keywords

Colloid, Titanium Oxide, Niobium, Gas Sensor, Spin Coating

Conflicts of Interest

The authors declare no conflicts of interest.

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