Color-tunable up-conversion emission from Yb3+/Er3+/TM3+/Ho3+ codoped KY(MoO4)2 microcrystals based on energy transfer

Tunable up-conversion luminescent material KY(MoO4)(2): Yb3+, Ln(3+) (Ln=Er, Tm, Ho) has been synthesized by a typical hydrothermal process. Under 980 nm laser diode (LD) excitation, the emission intensity and the corresponding luminescence colors of KY(MoO4)(2): Yb3+, Ln(3+) (Ln=Er, Tm, Ho) have been investigated in detail. The energy transfer from the Yb3+ sensitizer to Ho3+, Er3+ and Tm3+ activators plays an important role in the development of color-tunable single-phased phosphors. The emission intensity keep balance through control of the Ho3+ co-doping concentrations, white light was experimentally shown at KY(MoO4)(2): 20 mol% Yb3+, 0.8 mol% Er3+, 0.5 mol% Tm3+, 1.0 mol% Ho3+ phosphor with further calcination at 800 degrees C for 4 h under 980 nm laser excitation. The color tunability, high quality of white light and high intensity of the emitted signal make these up conversion (UC) phosphors excellent candidates for applications in solid-state lighting. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.