Experimental and DFT studies of structure, optical and magnetic properties of (Zn1−2xCexCox)O nanopowders

•Ce, Co co doped ZnO nanoparticles are produced using a microwave combustion route.•As synthesized nanoparticles have the wurtzite structure.•Morphological investigation revealed the nanoparticles in the range of 25–60 nm.•DRS measurements showed decrease in the energy gap with increasing dopants content.•DFT indicates Ce governs stability, while Co adjusts the magnetic characteristics.

A simple one-step microwave-assisted combustion method using urea as a fuel, was applied to develop the nanophase powders of ((Zn1−2xCexCox) O (x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05)). The results emphasize that by changing the codopant concentration it is feasible to fine-tune structural, morphological, optical and magnetic properties. The synthesized nanoparticles gave rise to new microstructures without changing the basic hexagonal wurtzite structure. The substitution of Ce and Co into ZnO lattice was confirmed from the shift in XRD peaks position, changes in peaks intensity, and cell parameters. Energy dispersive X-ray spectra confirmed the presence of Ce and Co within ZnO system; the weight percentage was close to their nominal stoichiometry. Ultraviolet–visible (UV–Vis) spectroscopy analysis indicated that the optical band gap decreased with the increase of Ce and Co codoping concentration. It is clear from SEM images that the average particles size decreased from 50 nm to 25 nm when codoping concentration was increased up to 0.05 M. Photoluminescence spectra exhibited the emission bands in ultra-violet and blue–green regions. Magnetization-Field (M–H) hysteresis loops revealed that the codoped nanopowders exhibited room temperature ferromagnetism (RTFM). Using first principles calculations, based on density functional theory, electronic and magnetic properties of codoped ZnO for different dopants concentration, were predicted. It is found that the observed RTFM is originated mainly from spin polarization of Co-d orbital, Ce-f orbital has partial contribution.

Graphical abstractMicrowave-assisted combustion method was used to develop the nanophase powders. The shift in the XRD peak position, changes in peak intensity, cell parameters, and cell volume confirms the substitution of Ce and Co into ZnO lattice. SEM images show that the average crystal size decreased from 50 nm to 25 nm when co doping concentration was increased. The vibrating sample magnetometer (VSM) revealed that the doped samples exhibited ferromagnetism at room temperature. Using first principles calculations, we predicted the magnetic and electronic properties of co-doped ZnO for different dopants concentration.Figure optionsDownload full-size imageDownload as PowerPoint slide