Nanostructured V 2 O 5 thin films prepared spray pyrolysis technique for NO 2 sensor

Nanostructured thin films of V2O5 are sensitive to change in their environment. V2O5 is successfully used as gas sensor due to the dependence of the electrical conductivity on the ambient gas composition. Nanostructured V2O5 thin films of different spray deposition time (5 min., 10 min., and 15 min.,) were deposited onto heated glass substrate at 350 o C by simple spray pyrolysis (SP) technique. Sensing elements of nonostructured V2O5 were annealed at 500 o C for 60 min. Characterization includes a different analytical technique such as, X*ray diffaractogram (XRD), energy dispersive X*ray analy sis (EDAX), and Field emission scanning electron microscope (FE*SEM). The average grain size observed from XRD and FF*SEM was found to be less than 24 and length of t he rod 370 nm respectively. The films sprayed for 10 min. was observed to be most sensitive (S = 531) to NO 2 for 500 ppm at 350 o C. The response and recovery time is 2 sec, 11 sec respectively.