a b s t r a c tGd 2 O 3 :Eu 3+ (4 mol%) nanophosphor co-doped with Li + ions have been synthesized by low-temperature solution combustion technique in a short time. Powder X-ray diffractometer (PXRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), UV-VIS and photoluminescence (PL) techniques have been employed to characterize the synthesized nanoparticles. It is found that the lattice of Gd 2 O 3 :Eu 3+ phosphor transforms from monoclinic to cubic as the Li + -ions are doped. Upon 254 nm excitation, the phosphor showed characteristic luminescence 5 D 0 → 7 F J (J = 0-4) of the Eu 3+ ions. The electronic transition located at 626 nm ( 5 D 0 → 7 F 2 ) of Eu 3+ ions was stronger than the magnetic dipole transition located at 595 nm ( 5 D 0 → 7 F 1 ). Furthermore, the effects of the Li + co-doping as well as calcinations temperature on the PL properties have been studied. The results show that incorporation of Li + ions in Gd 2 O 3 :Eu 3+ lattice could induce a remarkable improvement of their PL intensity. The emission intensity was observed to be enhanced four times than that of with out Li + -doped Gd 2 O 3 :Eu 3+ .

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Crystal structure of tetragonal BiOCl, field emission scanning electron micrographs, CIE chromaticity diagram and percentage of RhB dye degradation of Bi1−xEuxOCl.

A series of Bi1−xEuxOX (X = F and Br; x = 0, 0.01, 0.03 and 0.05) phosphors were synthesized at relatively low temperature and short duration (500 °C, 1 h).

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Gd(2)O(3) nanoparticles (27-60 nm) have been synthesized by the low temperature solution combustion method using citric acid, urea, glycine and oxalyl dihydrazide (ODH) as fuels in a short time. The structural and luminescence properties have been carried out using powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Raman, UV-Vis, photoluminescence (PL) and thermoluminescence (TL) techniques. The optical band gap values were estimated for as formed and 800 °C calcined samples. The band gap values in as-formed and calcined samples were found to be in the range 4.89-5.59 eV. It is observed that, the band gap values are lower for as-formed products and it has been attributed to high degree of structural defects. However, in calcined samples, structure becomes more order with reduced structure defects. Upon 270 nm excitation, deep blue UV-band at ~390nm along with blue (420-482 nm), green (532 nm) and red emission (612 nm) was observed. The 390 nm emission peak may be attributed to recombination of delocalized electron close to the conduction band with a single charged state of surface oxygen vacancy. TL measurements were carried out on Gd(2)O(3) prepared by different fuels by irradiating with γ-rays (1 kGy). A well resolved glow peak at 230 °C was observed for all the samples. It is observed that TL intensity is found to be higher in for urea fuel when compared to others. From TL glow curves the kinetic parameters were estimated using Chen's peak shape method and results are discussed in detail.

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