Green Synthesis and DFT study of Nickel Zinc Ferrite Nanoparticles: A Highly Sensitive Room Temperature VOC Sensing Material

Abstract

Abstract In the present communication, nanocrystalline nickel zinc ferrite (NZF) has been prepared by co-precipitation method in varied proportions and their alcohol (primary alcohols viz. ethanol, propanol and butanol) sensing behaviour at room temperature is studied. Nanocrystalline nickel zinc ferrite (NZF) Ni1-xZnxFe2O4 (where x = 0.3, 0.5 and 0.7) with varied molar concentration has been successfully prepared by coprecipitation method at controlled spin and temperature. The structural and surface morphological characterizations, porosity and surface activity of the prepared NZFs have been analyzed by Powder X-ray Diffraction (PXRD) and Field Emission Scanning Electron Microscopy (FESEM). The variations in electrical resistance of Ni0.7Zn0.3Fe2O4 (NZF1), Ni0.5Zn0.5Fe2O4 (NZF2) and Ni0.3Zn0.7Fe2O4 (NZF3) are measured with the exposure of 500 ppm ethanol, propanol and butanol vapours as a function of time at room temperature. 89% sensitivity is shown by NFZ1 for 500 ppm of the ethanol vapour at the same experimental condition. The sensing response followed the order of ethanol > propanol > butanol for all the three samples. The increasing trend of VOC (volatile organic substance) sensing properties by NZFs has been verified through extensive DFT (density functional theory) analysis by adopting PAW (projector augmented wave) technique. DFT calculation supports the pulling effect of Ni atoms in NZF nanoparticles which consequently increases the sensing properties of the prepared NZF nanomaterials. ELF (Electron localization function) study also supports the accelerated adsorption capacity of nickel doped nanoferrites.