Effect of La incorporation on the NH3sensing behaviour of ZnO thin films prepared using low-cost nebulizer spray technique

Lanthanum-doped zinc oxide (ZnO:La) thin films were deposited using a nebulizer spray technique with La concentrations 0, 1, 3 and 5 wt%. The structural, morphological and gas sensing properties were studied. All the film samples exhibit considerable ammonia sensing ability. The gas sensing results show that the ZnO:La film with 3 wt% of La doping exhibits remarkable sensing response and fast response/recovery times (39 s/11 s) for 100 ppm of NH(3)at room temperature. The reasons for the enhanced sensing ability of the doped films have been addressed with the help of the underlying mechanism, atomic force microscopy (AFM) and photoluminescence (PL) results.