Pechini sol–gel deposition and luminescent properties of SrLa1−xRExGa3O7 (RE = Eu, Tb) phosphor films

SrLa1−xRExGa3O7 (RE = Eu3+, Tb3+) phosphor films were deposited on quartz glass substrates by a simple Pechini sol–gel method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy, field-emission scanning electron microscopy, photoluminescence spectra, and lifetimes were used to characterize the resulting films. The results of XRD indicated that the films began to crystallize at 700 °C and crystallized fully at 900 °C. The results of FT-IR spectra were in agreement with those of XRD. Uniform and crack-free films annealed at 900 °C were obtained with average grain size of 80 nm, root mean square roughness of 46 nm and thickness of 130 nm. The RE ions showed their characteristic emission in crystalline SrLa1−xRExGa3O7 films, i.e., Eu3+5D0–7FJ (J = 0, 1, 2, 3, 4), Tb3+5D4–7FJ (J = 6, 5, 4, 3) emissions, respectively. The optimum concentrations (x) of Eu3+ and Tb3+ were determined to be 50, and 80 mol% in SrLa1−xRExGa3O7 films, respectively.