Cu2+ substituted Cr2O3 nanostructures prepared by microwave-assisted method: an investigation of its structural, morphological, optical, and dielectric properties

We have reported the preparation and characterization of both pure and Cu 2+ doped Cr 2 O 3 nanoparticles with different dopant concentrations by the simple, cost-effective microwave-assisted method. As-prepared samples have undergone various characterizations to get an insight into the Cr 2 O 3 nanoparticles. The XRD pattern showed the rhombohedral phase structure of Cr 2 O 3 with an average particle size of ±14 nm. The surface and morphology analysis (FESEM and TEM) revealed a nearly spherical shape with an average particle size of 30–50 nm and the presence of the elemental composition of Cr and Cu was confirmed by the EDAX spectrum. The optical properties (UV–Vis and PL spectra) of Cr 2 O 3 nanostructures were also studied, and results were found to support our further studies. Finally, electrical and dielectric characterization showed enhanced electrical conductivity concerning temperature and frequency. Highlights Pure and Cu-doped Cr 2 O 3 nanostructures were successfully synthesized. Spherical shape morphology with loosely agglomeration was observed. Electrical studies showed enhanced dielectric constant with temperature. High conductivity of Cu-doped Cr 2 O 3 was in consequence of polaron hopping.