Capacitive Mode Methanol Sensing by ZnO Nanorods Based Devices

Capacitive mode methanol sensing performance of ZnO hexagonal nanorods based MIS devices having diameters of 40-60 nm and lengths of 460-480 nm, is reported in this paper.ZnO nanorods were synthesized on p-Si substrate by chemical bath deposition method (CBD) using 50 ml aqueous solution of Zinc acetate dihydrate and HMT.The as deposited sensor with Pd catalytic contact in metal-insulator-metal (MIS) configuration offered 99% response magnitude (RM) in the temperature range of (300-325) º C towards 700 ppm methanol concentration.The response time (Rs:140s) and recovery time (Rc:110s) of the methanol sensor at 325º C were also obtained.The sensor was able to detect methanol even down to 10 ppm.