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14. Methanol sensing by SnO2 pellets prepared by chemical route method.

Author

Choudhury, Sandip Paul, Kumari, Navnita, Bhattacharjee, Debanjan, and Bhattacharjee, Ayon

Subjects
*METHANOL, *COPPER oxide, *NANOPARTICLES, *COPRECIPITATION (Chemistry), *TIN
Abstract

Synthesis of SnO2 and SnO2-CuO doped nanoparticles were carried out using chemical co-precipitation method. The precursor was SnCl4.5H2O. The XRD, SEM and EDAX of the nanoparticles were done, and the particle size was confirmed to be within 40nm. The powdered nanoparticles were then pelletized under a pressure of 13 Mp. Methanol was sensed with the pellets using a customized setup for 25, 50, 75 and 100ppm concentrations. It was observed that the sensitivity (S = Ra/Rg) showed appreciable variation at 375 °C and 275 °C for 75ppm and 100ppm of methanol respectively. [ABSTRACT FROM AUTHOR]

Published
2016
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15. Investigation of structural and electrical properties of CuO modified SnO2 nanoparticles.

Author

Kumari, Navnita, Ghosh, Arindam, and Bhattacharjee, Ayon

Subjects
*CRYSTAL structure, *COPPER oxide, *ELECTRIC properties of metals, *TIN oxides, *METAL nanoparticles, *COPRECIPITATION (Chemistry), *NANOCRYSTALS, *CRYSTAL grain boundaries
Abstract

Abstract: Nanocrystalline SnO2 was prepared by the co-precipitation method and doped with CuO. Crystallite sizes were estimated by Scherrer formula to be of the order of 90nm and lesser. A.C. conduction behaviour of the samples has been described by the different hopping processes. From impedance analysis multi-relaxation processes in the samples are evident. Shrinkage of Cole–Cole plots with increase in temperature is also observed in our case which shows role of grain and grain boundary effects in the conduction mechanism with rise in temperature. Dielectric constant decreases with frequency but increases with rise in temperature which is governed by different components of polarizability (deformational and relaxational polarization). Dielectric constant increases with rise in temperature but at higher frequency range it takes constant value. Impedance analysis is used to explain the effects of grain and grain boundary on transport mechanism of undoped and CuO modified SnO2 nanoparticles. [Copyright &y& Elsevier]

Published
2014
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