Development of nanostructured ZnO based gas sensors to use in Electronic Nose for biochemical compounds in black tea

Quantitative evaluation of aroma of black tea is a difficult task as no single sensor has been developed which can quantify the volatile aroma compounds. As an alternative, the array of sensors has been attempted to solve this problem involving the principle of neural-network for analysis of responses. To develop the array we have used nano-structured ZnO doped with various metals. In this presentation we describe the responses of Geraniol, Trans-2-Hexenal, Linalool Oxide & Linalool, the major aroma chemicals of black tea to doped and undoped ZnO with Pt metal. Nanostructured ZnO doped with and without Pt are synthesized through chemical process. The synthesized materials are characterized by XRD and SEM which confirm their nanostructure and phase purity. The synthesized sensors are heated in the temperature range of 200°C to 400°C and their responses towards volatile biochemical compounds like Geraniol, Trans-2-Hexenal, Linalool Oxide and Linalool are studied.