Synthesis and Study of Optical Properties of Dy³⁺ Doped Yellow Emitting Fluoroapatite for White -LED Applications

Abstract

In this article, we report that Ca8BiNa(PO4)6F2 fluorapatites, which were synthesised using a modified Pechini method and were first time doped with Dy3+ ions, are a promising material for yellow emitting phosphor for various optical applications. This fluorapatite has the ability to position activator Dy3+ ions in any of two cationic sites, namely M1 and M2, with distinct symmetries Cs and C3, respectively. After the sample was characterised, it was determined by XRD and Reitveld refinement analysis that it had crystallised into a hexagonal shape and belonged to the space group P63/m, matching the JCPDS file number 96-900-1879 According to the results of the PL analysis carried out by the Hitachi F-7100 spectrofluorophotometer, two emission peaks were obtained: one at 481 nm, which falls under the blue region, and the other at 575 nm, which falls under the bright yellow region. These two emission peaks correspond to the 4F9/2 to 6H15/2 and 4F9/2 to 6H13/2 transitions, respectively (Figure 5b). We suggest that the Ca8BiNa(PO4)6F2: Dy3+ can be employed as an excellent luminescent material with ultraviolet radiation as an excitation source for a variety of optical applications based on its optical properties. White light for WLED applications can be produced by a special phase doping of Dy3+ species in the host material with yellow and blue emission.