Nanocrystalline SnO2:F Thin Films for Liquid Petroleum Gas Sensors

Abstract

This paper reports the improvement in the sensing performance of nanocrystalline SnO2-based liquid petroleum gas (LPG) sensors by doping with fluorine (F). Un-doped and F-doped tin oxide films were prepared on glass substrates by the dip-coating technique using a layer-by-layer deposition cycle (alternating between dip-coating a thin layer followed by a drying in air after each new layer). The results showed that this technique is superior to the conventional technique for both improving the film thickness uniformity and film transparency. The effect of F concentration on the structural, surface morphological and LPG sensing properties of the SnO2 films was investigated. Atomic Force Microscopy (AFM) and X-ray diffraction pattern measurements showed that the obtained thin films are nanocrystalline SnO2 with nanoscale-textured surfaces. Gas sensing characteristics (sensor response and response/recovery time) of the SnO2:F sensors based on a planar interdigital structure were investigated at different operating temperatures and at different LPG concentrations. The addition of fluorine to SnO2 was found to be advantageous for efficient detection of LPG gases, e.g., F-doped sensors are more stable at a low operating temperature (300 °C) with higher sensor response and faster response/recovery time, compared to un-doped sensor materials. The sensors based on SnO2:F films could detect LPG even at a low level of 25% LEL, showing the possibility of using this transparent material for LPG leak detection.

Influence of fluorine doping on the microstructure, optical and electrical properties of SnO2 nanoparticles

“…The optical band gap value of tin oxide decreases from 3.88 to 3.44 eV with the increase of fluorine content. Impedance spectroscopy results indicate that the electrical properties are strongly dependent on presented as good material due to its superior physical and chemical properties for a large range of applications like gas sensors [11][12][13], photocatalysts [14] and solar cells [15,16]. Indeed, the properties of FTO powder are affected by the preparation process.…”

Microstructure analysis of spherical silicon solar cells with SnOx:Fy layers

“…Broad and characteristic peaks were observed in the range of 330-420 nm, and intensity of the characteristic peak was increased by annealing. In addition, the peak shape in the range of 330-380 nm, which is close to bandgap of SnO2 [22][23][24], was slightly changed by annealing. These results indicate that quality of the SnOx:Fy layers were improved by annealing.…”

Highly Sensing Properties Sensors Based on Ce-doped ZnO and SnO2 Nanoparticles to Ethanol Gas

“…Nano-semiconductor metal oxide gas sensors are inexpensive to produce compared to other sensing technologies, small in size, reliable, fast response, easy to used and can be used in real field. Among the semiconductor metal oxides materials, ZnO and SnO2 are the two of the most widely materials used in gas sensing applications [Chaisitsak 2011 andGupta et al 2010]. The advantages of the ZnO and SnO2 gas sensors are the high sensitivity, stability, novel shapes and low cost.…”