Nanocrystalline Ni0.6Zn0.4Fe2O4: A novel semiconducting material for ethanol detection

The structure and crystal phase of the nanocrystalline powders of Ni1−xZnxFe2O4 (0 ≤ x ≤ 0.5) mixed ferrite, synthesized by ethylene glycol mediated citrate sol–gel method, were characterized by X-ray diffraction and microstructure by transmission electron microscopy. Further studies by Fourier transform infrared spectroscopy were also conducted. Moreover, DC electrical properties of the prepared nanoparticles were studied by DC conductivity measurements. The response of prepared Ni1−xZnxFe2O4 mixed ferrites to different reducing gases (ethanol, hydrogen sulfide, ammonia, hydrogen and liquefied petroleum gas) was investigated. In particular, Ni0.6Zn0.4Fe2O4 composition exhibited high response to 100 ppm ethanol gas at 300 °C. Incorporation of palladium further improved the response, selectivity and response time of Ni0.6Zn0.4Fe2O4 to ethanol gas with the blue shift in the operating temperature by 25 °C.