title: Sol-gel synthesis and luminescence property of Sr4Al2O7:Re3+,R+(Re = Eu and Dy; R = Li, Na and K) phosphors for white LEDs.
abstract: Sr4Al2O7:Eu3+and Sr4Al2O7:Dy3+phosphors with alkali metal substitution were prepared using a sol-gel method. The effects of a charge compensator R on the structure and luminescence of Sr4Al2O7:Re3+,R+(Re = Eu and Dy; R = Li, Na and K) phosphors were investigated in detail. Upon heating to 1400°C, the structure of the prepared samples was that of the standard phase of Sr4Al2O7. Under ultraviolet excitation, all Sr4Al2O7:Eu3+,R+samples exhibited several narrow emission peaks ranging from 550 to 700 nm due to the 4f → 4f transition of Eu3+ions. All Sr4Al2O7:Dy3+,R+phosphors showed two emission peaks at 492 and 582 nm, due to the4F9/2→6H15/2and4F9/2→6H13/2transitions of Dy3+ions, respectively. The luminescence intensity of Sr4Al2O7:Re3+,R+(Re = Eu and Dy; R = Li, Na and K) phosphors improved markedly upon the addition of charge compensators, promoting their application in white light-emitting diodes with a near-ultraviolet chip.
authors.affiliation: College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, China.|Mineral Resources Chemistry Key Laboratory of Sichuan Higher Education Institutions, Chengdu, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Yu
authors.affiliation: College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, China.
authors.forename: Siyi
authors.initials: S
authors.lastname: Dai
authors.affiliation: College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, China.
authors.forename: Xianfei
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, China.|Mineral Resources Chemistry Key Laboratory of Sichuan Higher Education Institutions, Chengdu, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Long
mesh_terms: D005063:Europium; D008094:Lithium / Q000737:chemistry*; D049449:Luminescence; D049408:Luminescent Agents / Q000138:chemical synthesis* / Q000737:chemistry; D011188:Potassium / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry*
chemical_list: D049408:Luminescent Agents; D005063:Europium; D008094:Lithium; D012964:Sodium; D011188:Potassium
keywords: Sr4Al2O7:Re3+; charge compensation; photoluminescence; sol-gel method; white LED