Highly Sensitive Platinum Doped Nano SnO2 Based Thick Film CO Sensors

Synthesis of nanocrystalline SnO2 is carried out in a quartz tube furnace using thermal oxidation proces at optimized temperature of 900 degrees C. Synthesized nanophase SnO2 powder is used to fabricate thick film resistors using screen printing technology. The surfaces of the thick film resistors are modified by dip coating in platinum chloride solution of optimized 0.15 M for time period of 5 min. Sintering of the film is carreid out at 750 degrees C in a muffle furnace. The sensors are tested for 100 ppm concentration of CO. The sensores shows highest sensitivity towards, CO at 120 degrees C and it is five times higher than undoped SnO2 sensors. The characterization of the sensors is done using XRD, EDAX and SEM. The sensors are found to be extremely stable and repeatable with a response and recovery time of 10 and 52 s.