Triple-Layered Perovskite Niobates CaRNb3O10 (R = La, Sm, Eu, Gd, Dy, Er, Yb, or Y): New Self-Activated Oxides
Lin Qin †, Donglei Wei ‡§, Yanlin Huang *†(黄彦林), Sun Il Kim ‡, Young Moon Yu §, and Hyo Jin Seo *§‡
† College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, China
‡ Department of Physics and Interdisciplinary Program of Biomedical Engineering, Pukyong National University, Busan 608-737, Republic of Korea
§ LED-Marin Convergence Technology R&BD Center, Pukyong National University, Busan 608-739, Republic of Korea
Inorg. Chem. 2013, 52, 10407–10413
Niobates CaRNb3O10 (R = La, Sm, Eu, Gd, Dy, Er, Yb, or Y) were prepared by conventional high-temperature solid-state reaction. The formation of a single-phase compound with triple-layered perovskite-type structure was verified through X-ray diffraction (XRD) studies. The luminescence characteristics such as photoluminescence excitation and emission spectra, X-ray-excited luminescence (XEL), Stokes shift, decay curves, and color coordinates were investigated. The niobates can be efficiently excited by UV light and present luminescence behaviors with rich luminescence colors. Under excitation by ultraviolet radiation, CaRNb3O10 (R = La, Gd, Yb, or Y) exhibits strong blue luminescence due to the self-activation center of the octahedral NbO6 groups, even at room temperature. For the materials of composition CaRNb3O10 (R = Sm, Eu, Dy, or Er), the excitation at the host band produces a characteristic luminescence of rare earth ions, indicating a host–guest energy transfer process. CaRNb3O10 (R = Eu) has the strongest luminescence intensity, which can be efficiently excitated by near UV wavelength. It could be suggested to be a potential candidate for the application on near-UV excited white LEDs.
链接： //pubs.acs.org/doi/abs/10.1021/ic401854r
