Humidity Sensing Behavior and Characterization of CuWO ₄ Nanoparticles

Solution route precipitation technique was opted to synthesize the nanostructured copper tungstate by the incorporation of cupric ion solution to the aqueous sodium tungstate reagent. The size and surface of the synthesized nanostructured material is highly influenced by the concentration of cuprous ion as well as the tungstate solution. The structural pattern and chemical composition of CuWO4 nanoparticles were analysed by powder XRD and FESEM with EDX spectrum. The powder XRD and EDX pattern confirmed the elemental composition of the synthesized samples. FESEM images indicated that the particle was present in random size distribution. At 298 K, water vapour pressure thermostat was achieved in the range from 5% to 98% as a relative humidity (RH). By providing the DC conductance measurement as a relative humidity, the humidity sensing nature of the material was investigated and the sensitivity factor (Sf) value of the prepared CuWO4 was calculated at 298K (Sf=9640±100). It revealed excellent response time (60 sec) and recovery time (120 sec).