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Y2(1-x)Gd2xSiWO8?:?A (0=x=1; A=Eu3+, Dy3+, Sm3+, Er3+) phosphor films have been prepared on silica glass substrates through the sol-gel dip-coating process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG-DTA), atomic force microscope (AFM), scanning electron microscopy (SEM) and photoluminescence spectra as well as lifetimes were used to characterize the resulting films. The results of the XRD indicated that the films began to crystallize at 800 °C and crystallized completely at 1000 °C. The AFM and SEM study revealed that the phosphor films, which mainly consisted of closely packed grains with an average size of 90-120 nm with a thickness of 660 nm, were uniform and crack free. Owing to an efficient energy transfer from the WO42- groups to the activators, the doped lanthanide ion (A) showed its characteristicf-ftransition emissions in crystalline Y2(1-x)Gd2xSiWO8 (0=x=1) films. The optimum concentrations for Eu3+, Dy3+, Sm3+, Er3+ were determined to be 21, 5, 3 and 7 mol % of Y3+ in Y2SiWO8 films, respectively. The above lanthanide ions showed higher emission intensity for 0

Abstract: Rare earth ions (Eu3+, Ce3+ and Tb3+)-doped Y3Al5−x Ga x O12 (0≤x≤5) films were deposited on quartz glass substrates by a simple Pechini sol–gel method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG–DTA), atomic force microscopy, field-emission scanning electron microscope, photoluminescence spectra, and lifetimes were used to characterize the resulting films. The results of XRD indicated that the films began to crystallize at 900 °C and fully crystallized at 1000 °C. Both the results of FT-IR spectra and TG–DTA were in agreement with those of XRD. Uniform and crack-free films annealed at 1000 °C were obtained with an average grain size of 480 nm, a root mean square roughness of 13 nm and a thickness of 287 nm. The doped Ln3+ ions showed their characteristic emission in crystalline Y3Al5−x Ga x O12 films, i.e., Eu3+ 5D0-7F J (J=1, 2, 3, 4), Ce3+ 5d-4f and Tb3+ 5D3, 4-7F J (J=6, 5, 4, 3) emissions, respectively. The optimum doping concentrations of the Eu3+, Ce3+ and Tb3+ were determined to be 1.5, 1.0, and 4.0 mol% of Y3+ in Y3Al5O12 films, respectively. At the same time, the effects of the contents of Ga3+ (x) in Y3Al5−x Ga x O12 films on the luminescence properties of Ln3+ were also investigated. [Copyright &y& Elsevier]