title: Novel Garnet-structure Ca(2)GdZr(2)(AlO(4))3:Ce(3+) phosphor and its structural tuning of optical properties.
abstract: Aluminate garnet phosphors Ca2GdZr2(AlO4)3:Ce(3+) (CGZA:Ce(3+)) for solid-state white lighting sources are reported. The crystal structure and Mulliken bonding population of the CGZA:Ce(3+) have been analyzed. The larger 5d ((2)D) barycenter shift εc and smaller phenomenological parameter 10Dq of Ce(3+) in CGZA are related to the larger covalent character of Ce-O. The tuning spectral properties of the Ce(3+)-doped CGZA-based isostructural phosphors are presented. The splitting of cubic crystal field energy level (2)Eg in Ca2REZr2(AlO4)3:Ce(3+) (CREZA:Ce(3+)) (RE = Lu, Y, and Gd) increases as the radius of RE(3+) increases, and the splitting of (2)Eg may dominate the difference of spectroscopic red-shift D(A) in CREZA:Ce(3+). The splitting of the (2)Eg in CaGd2ZrSc(AlO4)3:Ce(3+) (CGZSA:Ce(3+)) phosphors increases seemly due to the decreasing of the covalent character of Ce-O. Thermal quenching properties of Ce(3+)-doped CGZA-based isostructural phosphors are also presented and analyzed. For CREZA:Ce(3+) phosphors, the increasing of the radius of RE(3+) results in an enhancement of thermal quenching. The quenching of CGZSA:Ce(3+) is obviously stronger mainly due to the smaller energy difference between the lowest 5d excited state and 4f ground state.
authors.affiliation: Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, China.
authors.forename: Xinghong
authors.initials: X
authors.lastname: Gong
authors.forename: Jianhua
authors.initials: J
authors.lastname: Huang
authors.forename: Yujin
authors.initials: Y
authors.lastname: Chen
authors.forename: Yanfu
authors.initials: Y
authors.lastname: Lin
authors.forename: Zundu
authors.initials: Z
authors.lastname: Luo
authors.forename: Yidong
authors.initials: Y
authors.lastname: Huang