From Structure to Luminescent Properties of B2O3-Bi2O3-SrF2 Glass and Glass-Ceramics Doped with Eu3+ Ions.

Karolina Milewska,Barbara Kościelska,Michał Maciejewski,Aleksandra Mielewczyk-Gryń,Anna Synak,Wojciech Sadowski,Marcin Łapiński

doi:10.3390/ma14164490

Abstract

Glass-ceramics with the composition B2O3-Bi2O3-SrF2 were synthesized by the conventional melt-quenching technique and subsequent crystallization of the parental glasses. The temperature at which the ceramization was carried out was selected based on differential scanning calorimetry (DSC) analysis. The structure of the studied materials and the formation of SrF2 nanocrystals were confirmed by the Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) techniques. It was found that the amount of strontium fluoride introduced into the parental borate-bismuth glass has a significant impact on the growth of SrF2 nanocrystals. In particular, the influence of the crystalline SrF2 phase on luminescence intensity and kinetics was studied using Eu2O3-doped samples. An increase in luminescence intensity was observed in the samples in which SrF2 nanocrystals were formed. This is most likely related to the fact that some of the Eu3+ ions were (after annealing of the glass) located in the crystalline structure of strontium fluoride. This was confirmed both by the luminescence lifetime obtained based on the luminescence decay curves and the calculated Judd–Ofelt parameters, Ω2 and Ω4. The results achieved confirm that the glasses and glass-ceramics described in this work could be considered as a new phosphor for light-emitting diodes (LEDs).

Highlights

Glass as a material for applications in optics and optoelectronics has enjoyed unflagging interest for many years
In summary, borate-bismuth glass-ceramics doped with Eu3+ ions, with SrF2 nanocrystals, were obtained
In the case of borate-bismuth glass, it is possible to obtain at least five stable crystalline phases of Bi2O3-B2O3 [11], and 10 mol % of SrF2 introduced into the glass is insufficient to block crystallization of the matrix

Summary

Introduction

Glass as a material for applications in optics and optoelectronics has enjoyed unflagging interest for many years. A lot of research is related to glasses and glass-ceramics with optically active dopants such as rare-earth ions, which are promising materials for use in white LEDs [1,2,3]. This is because of their unique combination of properties for excellent transmission in the visible and infrared spectral range, high refractive index, and good chemical and mechanical stability [4,5]. The addition of Bi2O3 to borate oxide changes the coordination number of the boron atoms [10,12,13], changing the properties of the resulting glass

Methods

Results

Conclusion