Study of In2O3 and α-Fe2O3 nano-composite as a petrol vapor sensor

In this experiment we studied morphological, structural and gas sensing properties of the In2O3-alpha-Fe2O3 nanocomposite films prepared by mechanical mixing. Iron oxide (alpha-Fe2O3 ) was prepared by co-precipitation method. We added 1 wt%, 3 wt%, 5 wt% and 7 wt% of In2O3 in synthesized iron oxide by mechanical mixing. Films of In2O3 additive and iron oxide were prepared using screen printing method. XRD study was employed to find out content and structure of the films. SEM analysis was carried out to understand film morphology. EDS analysis was carried out to understand elemental constituents of the films. Static gas sensing apparatus was used to study response of films for various gases. Properties like sensitivity, selectivity, response and recovery time were calculated. Petrol vapor sensors are not reported yet. At 250 degrees C these In2O3-alpha-Fe2O3 nano-composite films showed good response of 50% for petrol vapors as compared to other four gases. We discussed probable mechanisms for gas sensing.