Sensing characteristics of Molybdenum doped Zinc Oxide nanoparticles chemoresistor pellets towards black tea-biochemicals

Zinc oxide is a well established sensor material for detection of various organic molecules. In a quest of developing a sensor array for quality assessment of black tea, we have attempted developing pure and doped nanocrystalline zinc oxide pellet based sensors. The materials are sintered at 3500C and 5000C separately for six and three hours respectively. We obtained a highly reproducible sensor in 2% doped ZnO (calcined at 500°C for five hours and sintered at 350°C for 6 hours) for detection of tea biochemicals (i.e., Linalool, Linalool oxide, Trans-2-hexenal and Geraniol). XRD, FESEM, EDX and TEM characterisations confirm the formation of wurzite nanocrystals of approximately 20 nm. The sensitivity of this sensor is found maximum at an operating temperature of 350°C.