Humidity Sensing Investigations on Nanostructured Zinc Stannate Synthesized via Chemical Precipitation Method

ABSTRACT In this paper, nanoparticles of zinc stannate in different compositions were synthesized via chemical precipitation method. The as-synthesized material was characterized using differential scanning calorimetry. For the formation of crystalline zinc stannate, the synthesized material was annealed at 600°C. Surface morphologies of the samples were analyzed using scanning electron microscopy. The XRD pattern indicates the formation of nanocrystalline zinc stannate and it has a perovskite phase with an orthorhombic structure having a minimum crystallite size 4 nm. Pellets of the sensing materials were made by hydraulic press machine under a pressure of 616 MPa. Furthermore, the humidity sensing investigations of these sensing pellets were completed. Our results illustrate that zinc stannate in 1:4 weight ratio was most sensitive to humidity in comparison to other compositions under same conditions. Maximum sensitivity of the sensor was 3 GΩ/%RH. The results were reproducible up to 72% after 2 mon of ...