Upconversion emission and cathodoluminescence of Yb3+ ions activated BiOCl:Ho3+ phosphors

Upconversion (UC) emission and cathodoluminescence (CL) properties of Ho3+/Yb3(+)-codoped BiOCI phosphors were reported. Under 980 nm light excitation, all the samples exhibited strong green and red UC emissions corresponding to the (F-5(4), S-5(2)) ->(5) I-8 and F-5(5) -> I-5(8) transitions of Ho3+ ions, respectively. Furthermore, the UC emission intensity as a function of Yb3+ ion concentration was investigated to determine an optimum doping concentration and the UC mechanism was found to be a two-photon process. Additionally, excellent CL properties were observed in Ho3+/Yb3+-codoped BiOCI phosphors and the CL emission intensity increased with increasing the accelerating voltage and filament current. (C) 2016 Elsevier B.V. All rights reserved.