On the structural,optical and electrical properties of Cu2+ doped Zn0.94Cd0.06O nanomaterials

Nanoparticles of Cu²⁺ doped Zn_0.94Cd_0.06O oxide with formula Zn_0.94Cd_0.06-xCu_xO x = 0.0, 0.03, 0.05] were prepared via sol-gel auto combustion (SGAC) method at pH value of 10. Room temperature X-ray powder diffraction (XRD) patterns confirms that all the synthesized samples were single-phased polycrystalline with wurtzite hexagonal structure (P6₃mc). Crystallite size is estimated from XRD which was found to be 29–40 nm. Using Rietveld refinement of XRD data, the structure, space group and other structure related parameters were confirmed. The nanoparticle formation was confirmed via field emission scanning electron microscopy (FE-SEM) and elemental composition was verified through energy dispersive analysis of X-rays (EDAX). Raman spectroscopy reveals seven active phonon modes for both pristine Zn_0.94Cd_0.06O and Zn_0.94Cd_0.06-xCu_xO x = 0.03, 0.05]. The oxide formation is also conveyed through Fourier transformation of Infra-red (FTIR) spectroscopy. The bandgap using UV–Vis spectroscopy was found to be about 3.02 eV and 3.09 eV for Zn_0.94Cd_0.06-xCu_xO (x = 0.03, 0.05), 3.14 eV for pristine Zn_0.96Cd_0.06O. The dielectric studies confirmed high dielectric constant for Zn_0.94Cd_0.06O that decreases gradually on increasing Cu²⁺ doping concentration. The impedance analysis of all samples shows non-Debye character with spread of relaxation times.