Effect of Fe doping concentration on optical and magnetic properties of ZnO nanorods.

Herein, a facile low temperature, aqueous solution-based chemical method has been demonstrated for large-scale fabrication of Fe doped ZnO nanorods (ZnO:Fe) with a series percentage of Fe dopant. Interestingly, the SEM results reveal a uniform well dispersed synthesis of ZnO:Fe nanorods throughout the substrate. The x-ray diffraction result suggests that Fe substitutes Zn in the ZnO matrix and rules out the formation of any secondary phase. Selected area electron diffraction investigation verifies the single crystal, hexagonal wurtzite structure of the ZnO:Fe nanorods. Energy dispersive spectroscopy data confirm Fe doping of the ZnO nanorods with a concentration ranging from 0.9 to 2.2 at.%. The photoluminescence spectrum reveals a continuous suppression of defect related broad-band emission (I(D)/I(UV) = 1-0.11) by increasing the concentration of the dopant ion, which produces the quenching of surface defects present in the nanostructures. An enhancement in ferromagnetism (M = 0.15 × 10⁻²-0.24 × 10⁻¹ emu g⁻¹ at 2000 Oe) is found in doped ZnO nanorods.