Synthesis and up- conversion luminescence properties of a novel Yb3+, Er3+ co-doped Ca5Mg4(VO4)6 phosphor

A novel kind of Yb3+, Er3+ co-doped Ca5Mg4(VO4)(6) up-conversion (UC) luminescence phosphor was synthesized using a high-temperature solid-state reaction route. X-ray diffraction illustrated that pure phase Ca5Mg4(VO4)(6) were obtained in as-prepared un-doped and doped samples. The Ca5Mg4(VO4)(6) host is a kind of novel self-activated yellowish-green luminescent material, which has a broad emission band ranging from 400 to 800 nm with the peak at 546 nm under 367 nm excitation. Two intense green emission bands peaking at 523 (H-2(11/2) -> I-4(15/2)) and 552 nm (S-4(3/2) -> I-4(15/2)) as well as a weak red one (F-4(9/2) -> I-4(15/2)) around 658 nm were observed under 975 nm excitation in Yb3+, Er3+ co-doped Ca5Mg4(VO4)(6) because of the existence of energy transfer from Yb3+ to Er3+ ions, which was demonstrated using the decay lifetimes. The luminescence and energy transfer (ET) mechanisms were clarified in detail and the generations of the up-conversion emissions in the green and red regions were demonstrated to be both double photon excitation processes. (C) 2017 Elsevier B.V. All rights reserved.