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This paper reports on synthesis of undoped and Dy3+-doped cubic Y2O3 nanopowder via a neoteric and conducive citrate sol–gel technique. The size and morphology of prepared nanocrystallites are explored using XRD, TG-DSC, FTIR, FESEM, and HRTEM. Rietveld refinement is employed to affirm the preparation of as-synthesized Y2O3 nanocrystallites with cubic phase. The optical behavior of as-synthesized Y2O3, Dy3+-doped Y2O3 samples are studied in terms of absorbance, PL, and CIE coordinates. It is revealed that position of absorption peak is shifted towards higher wavelength side when Dy3+ ions are introduced in Y2O3 and further on annealing. In PL spectra, prominent emission is achieved in blue region at 485 and 369 nm under direct and indirect excitation wavelengths. Catalytic performance of the samples is also examined to de-colorize cotton blue dye. Annealing for a long time generated defect states which are helpful to accelerate the photocatalytic efficiency of the prepared nanopowder. [ABSTRACT FROM AUTHOR]

The main focus of this study is to synthesize Mn-doped CdO nanopowder and explore its optoelectronic behavior via a temperature-dependent mechanism. Mn-doped cadmium hydroxide nanopowder is primarily evolved using essential precursors by co-precipitation. Nanocrystalline powder of Mn-doped cadmium oxide is acquired after thermal treatment of the corresponding hydroxides. Various characterization tools have been used to examine the prepared samples. In the differential thermal analysis (DTA), a sharp endothermic peak was observed at 190°C and confirmed the Mn-doped hexagonal Cd(OH)2 nanostructure. In most annealed samples (at 750°C), this structure was modified to almost spherical cadmium oxide (CdO) nanoparticles. The surface images of electron micrographs clearly expressed the fabrication of nanorod-type structure, and the presence of cadmium (Cd), manganese (Mn), oxygen (O) have been confirmed by energy dispersive spectroscopy (EDS). The band gap energy of these nanorod-like structures is obtained in the range 3.07 − 3.39 eV, and further photoluminescence (PL) results emphasized the broad bands in the blue-green region. Electrical characteristic curves inferred that the resistivity is reduced while current density is significantly increased using proper thermal treatment. Such semiconductor nanocrystallites can be utilized as a potential alternate of modern oxides with better conductivity and superior luminescence in the visible region. [ABSTRACT FROM AUTHOR]