Highly sensitive and selective room temperature acetone sensing properties of Co doped ZnO nanostructure films

This work presents an improvement in room temperature gas sensing properties of ZnO thin film samples as an impact of cobalt doping. The response of films towards various gases (xylene, toluene, isopropanol, methanol, ethanol and Acetone) were studied. Thin films samples were prepared using the spray pyrolysis technique. XRD patterns revealed hexagonal (wurtzite) structure of prepared film samples. UV–Vis spectra showed the reduction of the energy band gap with cobalt doping. Different modes in the Raman spectra were observed in the vibrational analysis of the samples. A spindle-like morphology with enhanced surface granularity is observed with cobalt incorporation. This research extensively studied the response of thin films to different acetone gas concentrations at room temperature. At 50 ppm acetone concentration, 3% Co doped ZnO thin films showed a maximum response of 185. Also, Co doped ZnO film shows good selectivity towards acetone as compared to other gases. The obtained results brought attention to the potential utilization of cobalt doped ZnO thin films in developing gas sensing devices.