High luminescence quantum efficiency of green mesophase silicate thin film incorporated with rare earth complex

Mesophase silica thin film doped with in-situ formed binary terbium (Tb) complex was synthesized through a simple one-step evaporation-induced self-assembly method. In this process, the precursors of rare earth complex and surfactant were added into hydrolyzed tetramethoxy-silane (TMOS) together and the inorganic/organic mesophase thin film was formed after spin coating. The mesophase structure was characterized as a 2D-hexagonal structure by X-ray diffraction (XRD) analysis. The excitation spectra (λem = 544 nm) and emission spectra (λex = 315 nm) indicated that the binary complex, Tb(SA)3, formed in-situ during the formation of the film. Under the UV excitation, the mesophase silica thin film showed bright and consistent green luminescence. The luminescence quantum efficiency of the hybrid thin film was confirmed to be 35.2%.