Papers by Keyword: SO₂ Gas

Abstract: This report describes the preparation of gas sensors based on SnO₂ semiconductor nanostructure thin films synthesized using chemical bath deposition (CBD) technique. As the rapid demand of the gas sensors based on the semiconductor materials, there have been significant efforts to improve the performance of the semiconductors sensors. SnO₂, which has good electrical and mechanical properties, is one of the potential materials to be developed. In the present study, the SnO₂, prepared using CBD technique with stannous cloride as precursors, has nanopattern that give much SO₂ particles to access into the semiconductor surface. The resulting nanostructure SnO₂ thin films have been confirmed by X Ray Diffractions (XRD), Energy Dispersive Spectroscopy (EDS) and Scanning Electronic Micrsocopy (SEM). The as fabricated SnO₂ thin films sensors were then characterized as SO₂ gas sensors in various concentrations for several different operating temperatures. The sensors have good sensitivity as low as 30 ppm of SO₂ gas at the optimum temperature of 200⁰ C.

Abstract: This paper presents the corrosion of potassic glasses by SO2 gas at high-temperature. The corrosion phenomenon of potassic glass is well-known for medieval stained-glass windows under natural conditions of weathering [1]. Nevertheless the corrosion is also possible without humidity at high temperature in presence of polluting gas such as SO2 gas in the furnace. All source of SO2 gas can thermodynamically involve the main formation of K2SO4 and other alkaline salts such as Na2SO4. This corrosion manifests itself by the presence of “white flakes” in the bulk glass and this defect leads to discard of the piece for a crystal-maker like Daum. Alkali sulphate formation was determined by using scanning electron microscopy and presents a very particular morphology. This study allowed underlining on, one hand the influence of the temperature and on the other hand the role of gas concentration on the formation of the potassium sulphate. Thermal analysis technique (TGA) was carried out in order to understand the corrosion chemical kinetic of potassic glasses by SO2 gas.