Relative Humidity Sensing Studies of WO3-ZnO Nanocomposite
Paper reports morphological and humidity sensing studies of WO3 and WO3-ZnO nanocomposite pellets prepared in the weight ％ ratio of 10:1, 4:1 and 2:1 by solid-state reaction route. The pellets have been annealed at temperatures of 300-500℃. XRD pattern shows peaks of ZnWO4 formed due to solid state reaction between WO3 and ZnO. SEM micrographs show that the sensing elements manifest porous structure. Granulation and tendency to agglomerate seen in the SEM micrograph are due to the presence of zinc ions in ZnWO4. Nanoparticles are having their sizes in the range 37-182 nm. The average Kelvin radius at 20ⅹC room temperature is 27 . Humidity sensing application of the pellets has been studied in a humidity control cabinet. It is observed that as relative humidity increases, there is decrease in the resistance of pellets in the range 10-85％ RH. Sensing element of WO3-ZnO in 2:1 weight ％ ratio shows best results in 10-85 ％ relative humidity range. The average sensitivity of this sample is 1.20 Mз/％RH. This sensing element shows good reproducibility, low hysteresis and less effect of aging.
Humidity WO3 ZnO Nanocomposite Kelvin Radius Metal Oxides Sem XRD
N K Pandey A Tripathi K Tiwari A Roy
Sensors and Materials Research Laboratory, Department of Physics, University of Lucknow, Lucknow-226007, U.P. India
国际会议
青岛
英文
365-368
2009-10-09（万方平台首次上网日期，不代表论文的发表时间）