Structural, magnetic and optical properties of chemically synthesized Zn_0.98Fe₀₀₂O dilute magnetic semiconductor nanoparticles

A dilute magnetic semiconductor (DMS) is a transition metal-doped semiconductor having both magnetic and semiconductive properties. Dilute magnetic semiconductors are gaining attention as potential microelectronics options due to their unusual spin-dependent magneto-electro-optical capabilities. Because of their potential applications in spintronic devices, dilute magnetic semiconductors are made by fractionally substituting magnetic transition metals for nonmagnetic semiconductor cations. Doped ZnO is the most promising dilute magnetic semiconductor material for use in spintronics. Doping is a method of enhancing the magnetic, optical, and electrical properties of semiconductor nanoparticles. The current study focuses on synthesizing iron-doped ZnO nanoparticles (NPs) by an arrested precipitation process with a doping concentration of 2 mol%. Stoichiometric ratio of zinc nitrate and iron nitrate was used as the precursors and by adding 1 M NaOH solution the precipitates of ZnO NPs were generated. Obtained samples were washed thoroughly using distilled water and propanol. Finally, pristine as well as Fe-doped ZnO NPs were annealed for 2 h at 400 °C. The structural, optical, morphological features were explored by XRD, FE-SEM and UV-Visible spectroscopy techniques. XRD analysis revealed that the NPs possessed hexagonal wurtzite crystal structure. The crystallite size and lattice strain were determined by the Debye-Scherrer equation. The crystallite size was measured to be 36 nm and 25 nm for ZnO and Zn_0.98Fe_0.02O NPs respectively. Absorption spectra were recorded for both the samples and band gap were 3.27 and 3.29 eV for pristine and 2 % Fe doped ZnO NPs respectively. Weak ferromagnetic property was observed after doping ZnO by Fe as seen by hysteresis loop recorded at room temperature. Optical and magnetic attribute of Zn_0.98Fe_0.02O nanoparticles present it as potential candidate for spintronics applications.