Structural, optical and room-temperature ferromagnetic properties of Fe-doped CuO nanostructures

•Fe-doped CuO nanostructures were synthesized by a simple and green method.•The Fe-doping has obvious effect on the morphology of the pure CuO.•The optical property of the various nanostructures was studied.•Saturation magnetization increased with the increase of the Fe content.

Pure CuO and Fe-doped CuO nanostructures with different weight ratios (0.5, 1.0, 1.5, and 2.0 at wt% of Fe) were synthesized via the microwave combustion method. The synthesized samples were characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy and vibrating sample magnetometry (VSM). XRD patterns refined by the Rietveld method indicated the formation of single-phase monoclinic structure and also confirmed that Fe ions successfully incorporated into CuO crystal lattice by occupying Cu ionic sites. Interestingly, the morphology was found to change considerably from nanoflowers to nano-rod and disk-shaped then to nanoparticles with the variation of Fe content. The optical band gap calculated using DRS was found to be 2.8 eV for pure CuO and increases up to 3.4 eV with increasing ‘Fe’ content. Photoluminescence measurements also confirm these results. The magnetic measurements indicated that the obtained nanostructures are found to be room temperature ferromagnetism (RTF) with an optimum value of saturation magnetization at 2.0 wt% of Fe-doped CuO, i.e. 1.2960×10−3 emu/g.

Graphical abstractA simple and rapid microwave-assisted combustion method was developed to synthesize Fe-doped CuO nanostructures. Various morphologies were obtained with increase in Fe content.Figure optionsDownload full-size imageDownload as PowerPoint slide