Preparation, structure and up-conversion luminescence properties of novel cryolite KYF:Er, Yb.

Cryolite is a suitable host for up-conversion luminescent materials due to its low phonon energy and good optical transparency. In this work, a novel up-conversion material KYF:Yb, Er with a cryolite structure was prepared successfully by a solid state method. The crystal structure, morphology, composition and up-conversion luminescence properties of the as-prepared sample were characterized by X-ray diffractometry (XRD), field emission scanning electron microscopy (SEM) and fluorescence spectrometer in detail. KYF:Er, Yb has a cryolite structure. Under 980 nm excitation, the as-prepared sample can generate slight green emission at 524 and 546 nm (attributed to H → I transition, S→I transition of Er) and strong red emission at 661 and 672 nm (corresponding to F → I transition, I → I transition of Er). All the green and red up-conversion emission of KYF:Er, Yb transfer and electronic transition process of the red and green light the sample emitted, the possible luminescence mechanism is discussed in this paper.