Abstract
SnO2-TiO2 (S-T) composites with different molar ratios were prepared by mechanical mixing followed by sintering at 700 °C for 4 h in air. The structural and microstructural properties of the composites were investigated using powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). S-T composites were investigated by introducing SO2 to test their chemical stability using PXRD and SEM coupled with energy dispersive X-ray (EDX) analysis. The sensing performance was measured at different temperatures using various SO2 concentrations (10–100 ppm). A composite comprising 25 mol% of SnO2 and 75 mol% TiO2 (S25-T75) exhibited the highest sensitivity comparing to other S-T composites studied under the presently investigated conditions. t90 (90 % of response time) was found to be ∼5 min for thick pellet (~2 mm in thickness). SO2 sensing mechanism has been explained through the band structure model.
Original language | English |
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Pages (from-to) | 1927-1935 |
Number of pages | 9 |
Journal | Ionics |
Volume | 22 |
Issue number | 10 |
DOIs | |
Publication status | Published - 1 Oct 2016 |
Keywords
- Composites
- Gas sensors
- n-n junction
- Selectivity
- Semiconductors
- SnO-TiO
- SO sensor