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

Abstract

In present communication, nanocrystalline nickel zinc ferrite (NZF) has been prepared by spin controlled coprecipitation method in varied proportions to study the alcohol (primary alcohols viz. ethanol, propanol and butanol) sensing behaviour at room temperature. Nanocrystalline nickel zinc ferrite (NZF) Ni1-xZnxFe2O4 (where x = 0.3, 0.5 and 0.7) are subjected to the structural and surface morphological characterizations, porosity and surface activity through 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 time function at room temperature. 89% sensitivity is detected by NFZ1 for 500 ppm of ethanol vapour. 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 NZFs. ELF (Electron localization function) study also supports the accelerated adsorption capacity of nickel doped nanoferrites.