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This work presents the result of structure investigations of V2O5nanorods grown from thin films and powders prepared by sol-gel method. To examine the best temperature of nanorods crystallization, thin films deposited by spin-coating method on quartz glass or silicon substrates and bulk xerogel powders were annealed at various temperatures ranging from 100°C to 600°C. The structure of the samples was characterized by X-ray diffraction method (XRD), scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and mass spectroscopy (MS). The rod-like structure of V2O5was obtained at 600°C on both quartz glass and silicon substrates and also from the bulk xerogel. The growth process and the effect of annealing treatment on the nanostructure are briefly discussed.

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Structural and thermal properties of xMnO−(100− x)B 2 O 3 (where x = 40, 50 and 60 mol%) glass samples have been investigated with the employment of various techniques. Fourier transform infrared spectroscopy results revealed the influence of MnO on glass matrix. Decrease of B-O bond-related band intensities has been observed. MnO addition was found to introduce broken [BO 2 O − ] n chains. Differential scanning calorimetry (DSC) measurements presented decreasing T g that indicates depolymerization of glass matrix in the considered compositional range. Moreover, thermal stability (TS) parameter has been evaluated using the DSC technique. It slightly decreased with MnO content. X-ray photoelectron spectroscopy results provided the evidence for Mn 2+ and Mn 3+ presence. Multiplet splitting, close to that of MnO, has been observed. It has been concluded that most of the manganese ions existed in the divalent state. Photoluminescence study revealed that manganese ions are tetragonally coordinated in a glassy matrix.

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Glass systems of 73TeO 2 -4BaO-3Bi 2 O 3 -2Eu 2 O 3 -xAg (in molar ratio where x = 0, 1, 2, and 3) compositions have been successfully synthesized. Silver nanoparticles were obtained with the employment of heat treatment (HT) procedure executed at 350 ∘ C. Glass transition temperatures of different compositions have been determined through DSC measurements. XRD results presented characteristic amorphous halo indicating lack of long range order in the samples. FTIR structural studies revealed that glass matrix is mainly composed of TeO 3 and TeO 4 species and is stable after different applied heat treatment times. X-ray photoelectron spectroscopy (XPS) measurements confirmed that in selected samples part of Ag ions changed oxidation state to form Ag 0 species. TEM measurements revealed nanoparticles of size in the range of 20-40 nm. UV-vis absorption results demonstrated characteristic transitions of Eu 3+ ions. Additionally, UV-vis spectra of samples heat-treated for 6, 12, 24, and 48 hours presented bands related to silver nanoparticles. Photoluminescence (PL) studies have been performed with excitation wavelength of exc = 395 nm. Obtained spectra exhibited peaks due to 5 D 0 -7 F J (where = 2, 3, 4) and 5 D 1 -7 F J (where = 1, 2, 3) transitions of Eu 3+ . Moreover, luminescence measurement indicated enhancement of rare earth ions emissions in several of the annealed samples. Increase of emission intensity of about 35% has been observed.