The use of plants to make functional nano materials provides an environmentally friendly manner to produce these materials. In this study, γ-Fe₂O₃ nanoparticle biosynthesis has been achieved using the leaf extract of Dalbergia sissoo. The phytochemicals present in the leaf extract served as both reducing and stabilizing agents during the formation of the nanoparticles. The characterization of the nanoparticles using X-ray diffraction indicated that they are a cubic spinel material and contain an average crystallite size of 11.3 nanometres. The structural characterization of the nanoparticles using Fourier Transform Infrared Spectroscopy showed Fe-O lattice vibrations and that the surface of the nanoparticles contained organic functional surface groups. The characterization of the nanoparticles using Field Emission Scanning Electron Microscopy showed quasi-spherical formation and limited number of agglomerated nanoparticles as a result of annealing. The characterization of the nanoparticles using Ultraviolet-Visible Spectroscopy demonstrated that they have a strong ultraviolet light absorbance and photocatalytic properties. Evaluation of the direct and indirect band gap through characterization of the nanoparticles indicated that quantum confinement effects are present. The production of thin films through drop casting of the nanoparticles exhibit a smooth morphology. Electrical characterization of the thin films demonstrated linearly behaving–current voltage characteristics in addition to dependence upon temperature with regard to their conductivity. Arrhenius analysis resulted in determining an extremely low activation energy (0.1736 eV) for the electrical behaviour of the thin films produced in this study. The results obtained in this study suggest that the biosynthesized γ-Fe₂O₃ nanoparticles display properties suited for use in various sensing, photocatalytic functions, and for use in low-temperature electronic applications.
Kumar et al. (Thu,) studied this question.