Nanocrystalline CopperNickelZinc Ferrite: Efficient Sensing Materials for Ethanol and Acetone at Room Temperature

摘要

Nanostructured CuNiZnFe2O4 in varied molar concentrations is synthesized by the rate-controlled co-precipitation method. The powder X-ray diffraction pattern and the analysis of their micrographs have confirmed the Single-phase structure of the prepared samples. Field emission scanning electron microscopy study reveals the surface morphology of the samples with nanosized grains and open pores. The average grain size of both the prepared samples is found to be 24 and 25 nm, which is obtained by the histogram analysis of high-resolution transmission electron microscopy micrographs. The dc magnetic measurements and Mössbauer spectroscopic studies together reveal that both the samples are magnetically well ordered at the room temperature with superparamagnetic relaxation due to finite size effect. The ethanol and acetone sensing characteristics of the prepared samples are studied at room temperature by conductive measurements. The maximum sensitivity of 77% is observed for 500 ppm of acetone vapor by Cu0.5Ni0.25Zn0.25Fe2O4 (CNZ1), whereas a sensitivity of 75% is observed for 500 ppm of ethanol vapor by Cu0.25Ni0.5Zn0.25Fe2O4 (CNZ2). Moreover, a quick and good response of acetone vapors by CNZ1 and ethanol vapor by CNZ2 within 10 min is also noticeable. The sensor responses are quite stable and highly reproducible.