Up- and down-conversion luminescence in the oxyfluoride glass ceramics containing Ba 2+1.5xYb 1-xF 7:Tb 3+ nanocrystals

Abstract

Transparent oxyfluoride borosilicate glass ceramics containing Ba 2+1.5xYb 1-xF 7:Tb 3+ nanocrystals were successfully prepared by a melt-quenching method with subsequent heat treatment. The precipitated crystalline phase in the glass matrix changed gradually from BaF 2 to Ba 2+1.5xYb 1-xF 7 with the increase of YbF 3 content, which was confirmed by the results of XRD, HRTEM and EDX measurements. The ultraviolet and visible up-conversion and near-infrared quantum cutting down-conversion emissions were observed and interpreted. These materials could be used to modify the solar spectrum and enhance the silicon solar cell efficiency by the up-conversion and down-conversion luminescence of Tb 3+-Yb 3+ couples in the oxyfluoride borosilicate glass ceramics. © 2012 Elsevier B.V. All rights reserved.