Developing Molybdenum Doped Zinc Oxide Nanoparticles’ Sensors for Quality Assessment of Black Tea

Abstract

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, developing pure and molybdenum doped nanocrystalline ZnO-based sensors. The effect of changing the sintering duration and time has been studied. FESEM, EDS and XRD characterisations confirmed the formation of wurzite nanocrystals of approximately 20 nm. The 2% molybdenum doped ZnO (calcined at 500 °C for 5 h and sintered at 350 °C for 6 h) was found to be the best of all sensors we prepared for detection of tea biochemicals (viz., linalool, linalool oxide, trans-2-hexenal and geraniol). The sensitivity of this sensor was found maximum at an operating temperature of 350 °C.

Keywords: Sensors, doping, zinc oxide, black tea