Structure and optical properties of Eu3+, Gd3+ ions co-doped TiO2 phosphor thin films from anatase to pyrochlore

The structure and optical properties of the successful synthesis europium–gadolinium co-doped titanium dioxide luminescence thin films utilizing the sol–gel dip-coating method followed with thermal annealing in the range over 700–1000 °C for 1 and 2 h are presented. Effects of the higher Eu3+ ions concentration on the structure and optical properties of these film specimens were investigated using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. When the specimens annealed for 1 h, the results show thin films transformed from anatase phase to polycrystalline films consist of titanium dioxide contain pyrochlore phase with increasing annealing temperature. When annealing it for 2 h, formed a pure pyrochlore. Then, conducting Optical properties using UV–Vis absorption, and emission spectroscopy. A highly transparent thin film were fabricated, and it was found that Eu3+ ions were incorporated into the different formed phases. As a result, thin films showed efficient intense in red and orange–red emission from Eu3+ ions upon 292 nm light excitation. The morphology of the thin films exhibit homogenous films in various shapes. However, by increasing of Eu3+ ion concentration on the thin films composite resulted in reduction of the optical bandgap energy.