Raman spectroscopic study of ZnO/NiO nanocomposites based on spatial correlation model

Abstract

The effect of nickel concentration has been investigated in ZnO/NiO nanocomposites synthesized using the co-precipitation method. The X-ray diffraction and TEM measurements confirm the distinct phase of NiO in the ZnO/NiO samples. Furthermore, the Raman study shows the sharp modes at 99 cm⁻¹ and 438 cm⁻¹ corresponding to E^(low)₂, E^(high)₂ of hexagonal wurtzite ZnO structure and, 1080 cm⁻¹ associated to the two-phonon (2P) mode of NiO, respectively. We also compared the effect of Ni concentration on the formation of ZnO/NiO by analyzing E^high₂ Raman mode of ZnO with the help of spatial correlation model. The correlation lengths, broadening and asymmetry ratio obtained from the fitting showed good agreement with the experimental results.