CdFe2O4 films for electroresistive detection of ethanol and formaldehyde vapors

Spinel CdFe₂O₄ thin films were synthesized by spray pyrolysis. The structural probe studies confirmed the multicrystalline nature of the films with their spinel structure. The crystallites have sizes between 13 and 37 nm and island morphology. The energy dispersive spectroscopy reveals the presence of iron, oxygen and cadmium in the film. The room temperature electrical resistance of the thin film, best measured at a voltage of 10 V, decreases rapidly if it is exposed to vapors of formaldehyde or ethanol. The sensor has detection limits of 15 ppm for ethanol and of 15 ppm for formaldehyde and a sensitivity of 0.0387 nA per ppm of ethanol. Graphical abstract The perception on the interaction properties of alcohol vapors namely ethanol and formaldehyde in CdFe₂O₄ thin film. This work clearly suggested that the CdFe₂O₄ material is a good candidate for sensing ethanol and formaldehyde vapor molecules.