Tuning the Structural, Optical, and Photoluminescence Properties of Nano Zn_0.95Mg_0.05M_0.05O by Doping with Transition Metals (M = Cu, Ni, Mn)

Nano Zn 0.95 Mg 0.05 O and Zn 0.9 Mg 0.05 M 0.05 O (where M = Cu, Mn, Ni) were produced at low temperatures via solid-state reaction technique. Structure and microstructure of all samples were established using Rietveld analysis. X-ray diffraction, Fourier transform infrared spectroscopy, and photoluminescence studies revealed that M +2 ions are incorporated into the ZnO lattice by replacing Zn ions. In the visible-IR ranges, the absorption intensity of Zn 0.95 Mg 0.05 O sample is greatly enhanced from 20%-40% to 30%-80% depending on the dopant element in the host matrix. Optical band gap values of Zn 0.9 Mg 0.05 M 0.05 O were 3.27, 3.27, 3.34, and 3.24 eV for pure and doped with Cu, Mn, Ni samples, respectively. Different models were used to calculate refractive indexes of all samples. Nonlinear optical parameters reached their peak values in Zn 0.95 Mg 0.05 O doped with Ni, whereas they displayed their minimum values in Zn 0.95 Mg 0.05 O doped with Mn. Both the PL peaks positions and intensities are obviously changed upon doping. The CIE chromaticity coordinates plot indicates that the Zn 0.95 Mg 0.05 O sample displayed a cyan-green color. The color transitioned to blue, dependent upon the kind of dopant element. Following doping, there is a significant quenching of the PL intensity for both bands, which enhances the suitability of the doped samples for photocatalytic applications.