Physical and ethanol sensing properties of sprayed Fe2(MoO4)3 thin films

- Fe2(MoO4)3 thin film was prepared using chemical technique spray.
- From Rietveld refinement we found that our layer has a monoclinic structure with no other impurities.
- Fe2(MoO4)3 thin film was characterized by optical, electrical and gas sensing properties.
- The ac conductivity of the sprayed Fe2(MoO4)3 thin layers obeys the frequency power law.

Monoclinic Fe2(MoO4)3 thin films have been prepared by chemical spray technique deposited on glass substrates and investigated their physical properties. The obtained thin films were characterized by X-rays diffraction (XRD) using Rietveld's method which confirm the appearance of pure monoclinic Fe2(MoO4)3 thin films. Moreover, the surface morphological was investigated using scanning electron microscope (SEM), which showed the formation of porous microstructures with rough surfaces and spherical nanoparticles.The spectrophotometer UV-Vis-NIR reveals that the sample presents an optical gap equal to 2.0 eV. Electrical properties dependence on both temperature and frequency of the Fe2(MoO4)3 thin films have been reported. The ac conductivity plot showed a universal power law according to the Jonscher model. Activation energy values deduced from the relaxation frequency is of the order of 0.71 eV. Finally, Fe2(MoO4)3 thin films have been tested as sensitive films against ethanol vapor at different operating temperatures and gas concentrations. The films showed promising ethanol sensing behavior with good reproducibility and especially an excellent sensing performance at 275 °C.