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Mn:CeO2/PVP nanofibers were prepared via a simple electrospinning technique with heat treatment at 500°C. X-ray diffraction patterns revealed the formation of a face-centered cubic structure for pure and Mn:CeO2 nanofibers. Whole powder pattern modeling was applied to the x-ray diffraction data for pure and Mn:CeO2 nanofibers to determine the microstructure parameters (the crystalline domain size and the size distribution). The effect of Mn doping on the morphology features of the prepared nanofibers was assessed from the scanning electron microscopy (SEM) image analysis. The SEM images showed random fibers with no distinct alignment, with average fiber diameters of about 80–150 nm after calcination. FT-IR spectra of the Mn0.05Ce0.95O2 nanofibers showed stretching vibrations corresponding to Mn-O and Ce-O bonds. The optical absorption of pure and Mn:CeO2 nanofibers was studied using diffuse reflectance spectroscopy. The optical band gap was found to increase with increased Mn doping, which can be attributed to the quantum confinement effect. [ABSTRACT FROM AUTHOR]

In this work, X-ray diffraction analysis and optical properties of pure and Ba-doped ZnO nanoparticles prepared by the precipitation method were investigated. X-ray analysis was employed to evaluate the micro structural parameters of ZnO nanoparticles in terms of crystallite sizes and lattice strain by the Williamson–Hall method. The average crystallite size of Ba-doped ZnO nanoparticles estimated by the Williamson–Hall method varied as the doping concentration increased. The effect of Ba doping on the photoluminescence (PL) emission spectrum of ZnO was also investigated. The temperature dependence of the PL emissions was also studied, and it was found that at low temperature, the samples show stronger emissions than those at room temperature in both UV and visible regions. As a final point, the FT–IR reflection spectrum along with Kramers–Kronig (K–K) method and classical dispersion theory was applied to obtain optical properties of the samples at low frequency infrared regime. [ABSTRACT FROM AUTHOR]