Synthesis and Characterization of ZnO/ZnNb₂O₆ Nanocomposite and Its Application as Humidity and LPG Sensor

ABSTRACT

The present article reports the synthesis and characterization of ZnO/ZnNb₂O₆ nanocomposite and its humidity and liquefied petroleum gas (LPG) sensing behavior at room temperature. Pellets from the powder of synthesized material were calcined at 150, 300, 450, and 550°C for 3 h and tested for their humidity and LPG sensing ability separately. Each heat-treated pellet was exposed to humidity under controlled conditions, and variations in resistance with variations in humidity were measured. Similarly, heat treated pellets were exposed to LPG and variations in resistance were recorded. Electrical sensitivities of sensing material at different temperatures were also evaluated. After chemical mixing of niobium oxide with zinc oxide, the average sensitivity of a sensor increased from 8 to 19 MΩ/% relative humidity (RH) over the range from 10 to 95% RH at room temperature and in the case of LPG sensing, the maximum sensitivity was 12.

KEYWORDS:

• humidity
• nanostructures
• conduction
• SEM
• LPG
• sensors
• annealing

Acknowledgments

We are thankful to Professor U.D. Misra, Head, Department of Physics, University of Lucknow, for continuous encouragement, and financial support from U.G.C. as Major Research Project F. No. 36-265/2008 (SR) is acknowledged.