High-purity red up-conversion emission of Ba5Zn4Y8O21:Er3+,Yb3+ phosphor excited by 1550 nm laser diode

A novel Ba5Zn4Y8O21:Er3+,Yb3+ up-conversion phosphor was synthesized via solid-state reaction method. The up-conversion luminescence properties of the phosphor excited by 1550nm laser diode were investigated. Results showed that the characteristic emission peaks of Er3+ were located at 530, 550, 675, and 810 nm, which correspond to the transitions of H-2(11/2) -> I-4(15/2), S-4(3/2) -> I-4(15/2), F-4(9/2) -> I-4(15/2), and I-4(9/2) -> I-4(15/2), respectively. The up-conversion mechanisms were systematically studied through concentration and laser power dependence of the up-converted emissions. An evident tuning effect of Yb3+ on the luminescence of the phosphor was observed. An efficient red emission with high purity was obtained through the Er3+ -> Yb3+ -> Er3+ energy transfer process, and the intensity ratio of the red and green emissions could reach 62.28. Therefore, Ba5Zn4Y8O21:Er3+,Yb3+ can be an excellent up-conversion red emitter. (C) 2016 Elsevier Ltd. All rights reserved.