Present paper reports the growth mechanism of hexagonal ZnO nanocrystals (NCs) with their NO2 gas and humidity sensing. Thin film of ZnO was prepared using the zinc acetate with ethanol as precursors. Prepared thin film was annealed at 450°C for 2h which led to necking and coarsening of nanocrystals. Hexagonal crystalline nature of film was revealed by the XRD with the crystallite size ~71nm and AFM confirmed this fact. Film was exposed to NO2 and moisture separately and variations in resistance with the increasing %RH were recorded. The film gave highest sensing response for 20ppm NO2 as 150 and for moisture, the highest sensitivity was found as 10.91MΩ/%RH.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.