The present work describes modification in physical properties of Zn0.95Mn0.05O films by ion beam irradiation. Films were prepared by spin coating and annealed at 500°C. XRD patterns of these films show wurzite structure with good crystalline quality. However, low-energy irradiation could modify and induce new defect states. Characterization of those defects had been performed by analyzing the UV-Visible absorption spectroscopy and photoluminescence (PL) spectroscopy. Room-temperature PL emission of Zn0.95Mn0.05O film shows a broad UV emission and pronounced visible emission ~530 nm. At low temperature, broad UV band become more prominent; however, it is completely quenched after irradiation. For all irradiated films we noted only visible emission of comparable intensities, confined within the region 475 to 550 nm. Irradiated films are showing ferromagnetism at room temperature and most importantly the film irradiated at fluence F: 1016 ions/cm2 exhibit maximum saturation magnetic moment of 0.83 emu g-1. The magnetic response is strongly influenced by irradiation and we could say that magnetism is strongly correlated with intrinsic defects present in these films. Defect-induced formation of bound magnetic polarons actually control the ferromagnetic property of these films. These transparent ferromagnetic films could be used in optoelectronics.

The present work demonstrates synthesis and study of physical properties of chemically synthesized ZnO nanoparticles by co-precipitation technique. Detailed synthesis procedure had been described in the experimental section. Chemically synthesized ZnO samples were annealed at 300°C and 500°C. These samples have been characterized by doing X-Ray diffraction (XRD), photoluminescence (PL) and Raman spectroscopy. XRD patterns indicate wurzite structure of these samples. SEM pictures shows growth of grain size with annealing temperature treatment. The lattice parameters (a & c) of ZnO samples are showing increasing tendency with annealing treatment. PL spectra with excitation wavelength : λex=330 nm exhibit a broad and asymmetric UV band centred around 386 nm (~ 3.212 eV) and 390 nm (~ 3.179 eV) respectively for the 300°C and 500°C annealed samples. Broad UV emission band indicating that, it has defect related origin. The Raman spectra of these samples indicate that intensity of Raman peaks improves with annealing at the higher temperature. Possibly high temperature annealing (500°C) brings modification into the micro-structure. The micro-structure and optical properties of these synthesized samples are compared with that of pure ZnO powder samples. Finally correlation between structural and optical properties has been made based on the analysis of experimental data.

Present work demonstrate the structural and optical property study of Zn1-xNixO (x= 0.03, 0.05) nanoparticles (NPs). These samples have been prepared by simple chemical co-precipitation method. Finally these samples are annealed at 500°C for 3 hours. Structural characterization has been performed by doing X-Ray diffraction (XRD) at room temperature. The XRD patterns confirm the hexagonal wurzite structure for these samples. We have estimated the lattice parameters (a & c) and determine the c/a ratio of respective samples after structural analysis. Morphology of these nanoparticles has been investigated by performing SEM. In addition UV-visible and Photoluminescence (PL) study has been performed. PL emission spectra show a broad UV emission peak. Doping at the Zn-site by Ni ions could induce inter-band levels within the band gap. Transition between those levels may responsible for broadening of the UV peak. In addition defect mediated visible emission has also been observed in the PL study. Further to investigate the effect of doping on microstructure, Raman spectra of Zn1-xNixO samples are taken. Wurzite ZnO belongs to space group: C4 6v and consequently six first order phonon modes are expected to appear in the Raman spectra. Raman scattering has been analysed according to the existing literature and details of analysis are presented in this work.