Up-conversion phosphors: a short review

Abstract

This article reviews the upconversion phosphors based on their ability to emit various peaks corresponding to different colors in the visible range. The review suggests that these upconversion phosphors have a wide range of applications in the field of medical science and display devices especially. The study suggests that Erbium (III) and Ytterbium (III) have the capability to transfer energy gained from the excitation source to other co-dopants. Hence the co-dopants gain additional energy apart from the excitation sources which is usually 980 nm (near IR) and retain more energy than the energy provided by the excitation source. The mechanism of upconversion was also discussed. Most of the research used at least two dopants with the host for preparing an upconversion phosphor when they function like sensitizers and activators.