Impact of Mg 2+ substitution on the band gap energy, urbach energy, structure, and optical behavior of copper chromites nanoparticles

The current study describes the physicochemical properties of CuCr2O4 that is undoped and doped with magnesium using a microwave technique. Thioglycolic acid was the chelating/gelling agent that was employed. As a result, the products are characterized using Fourier transform infrared spectroscopy, electron microscope analysis, and X-ray diffraction. Using the Fd3m space group and lattice parameter a = 8.3472 Å, a Rietveld refinement study verified the formation of the single-phase cubic structure in CuCr2O4. SEM/TEM confirms the nanorods to nanoflakes in both pure and doped samples. According to experimental UV-Vis spectra, as Mg increases, the optical band gap (Egap = 1.95 eV to 2.59 eV) increases as well. An increase in Mg doping inside urbach energy was directly correlated with band gap energy. The optical properties of the absorbance spectra were investigated for both doped and undoped samples. Cu-O-Cr/Mg bonding is verified through Fourier transform infrared (FTIR) analyses. These chemically synthesized single-phase doped and undoped samples demonstrate the success of magnesium doping in the CuCr2O4 lattice. Both doped and undoped samples exhibit potential as building blocks for the creation of optical limiters with low threshold counts. According to optical studies, Cu-O-Cr/Mg has the best qualities and can be used in a wide range of optoelectronic applications.