Structural, Morphological, Optical and Magnetic Studies of Cu-Doped ZnO Nanostructures

In the present work, Cu-doped ZnO nanostructures (Cu% = 0, 1, 5) have been prepared using microwave-assisted chemical route synthesis. The synthesized nanostructures were investigated through structural, morphological, optical, and magnetic characterizations. The results of the X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and selective area electron diffraction (SAED) patterns confirmed that all of the samples exhibit the single-phase polycrystalline hexagonal crystal structure. The XRD results infer a decrease in the lattice parameters (a/c) by increasing the Cu% doping into ZnO. The field emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray (EDX) spectroscopic measurements revealed the formation of nanostructures, showing the major elemental presence of Zn and O in the samples. The photoluminescence (PL) spectra exhibited photoemission in the UV and blue-green regions. With the increase in the Cu%, the photoemission in the UV region is reduced, while it is enhanced in the blue-green region. Raman spectra of the Cu-doped ZnO nanostructures displayed a blue shift of the E-2(High) mode and an increase in the peak intensity of E-1(LO), indicating the doping of Cu ion in the ZnO lattice. The dc magnetization measurements demonstrated the ferromagnetic behavior of all of the samples with an enhanced ferromagnetic character with increasing Cu%.

Automated summary

In this study, Cu-doped ZnO nanostructures were prepared using a microwave-assisted chemical route synthesis. The synthesized nanostructures were characterized structurally, morphologically, optically, and magnetically. The results showed that the samples had a single-phase polycrystalline hexagonal crystal structure, with a decrease in lattice parameters by increasing Cu% doping. The samples exhibited photoemission in the UV and blue-green regions, with changes in these regions caused by Cu doping, and Cu ions successfully incorporated into the ZnO lattice. All of the samples exhibited ferromagnetic behavior, with enhanced ferromagnetic character with increasing Cu%.