Structure and optical properties of nano-ZnMn2O4/CuS solid solution heterostructure

Nano-ZnMn2O4 sample was coupled with nano-CuS using co-precipitation and thermolysis methods. All X-ray patterns for different values of alloying parameter (x) in (1-x) ZnMn2O4/xCuS (x = 0, 0.1, 0.15, 0.2) system, disclosed only single tetragonal ZnMn2O4 (ZMO) phase. Rietveld refinement examined the distortion in tetrahedral and octahedral sites of ZMO upon coupled with CuS. The cation distribution between different sites was also investigated using Rietveld analysis method. The cell parameters were affected by the composition of the sample and dragging effect. The effect of solid solution between ZMO and CuS, on tetrahedral and octahedra bands of ZMO phase was studied. X-ray photoelectron spectroscopy spectra were measured to confirm the incorporation of Cu and S ions into the ZMO lattice and to determine the oxidation states of different ions. The optical band gap energies for (1-x)ZnMn2O4/xCuS samples are 2.49, 2.57, 2.61, and 2.55 eV; x = 0, 0.1, 0.15, and 0.2, respectively. The effect of the insertion of Cu and S ions in the ZMO lattice on the different optical parameters and emitted colors was explored using UV diffused reflectance and photoluminescence spectrophotometer techniques. [GRAPHICS]