Effect of the Fluorine Substitution for –OH Group on the Luminescence Property of Eu3+ Doped Hydroxyapatite

Abstract

In this study, different fluoridated hydroxyapatite doped with Eu3+ ion nanoparticles were prepared by the hydrothermal method. The relationship between luminescence enhancement of Eu3+ ions and a fluorine substitution ratio for hydroxyl group in hydroxyapatite was discussed. Moreover, the effect of fluorine substitution for a hydroxyl group on phase composition, crystallinity, and crystal size was studied. Phase composition and chemical structures were identified by X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) Spectroscopy analyses. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) patterns were performed to analyze the morphology and particle size. X-ray Photoelectron Spectroscopy (XPS) patterns were observed to analyze fluorine substitution for the hydroxyl group and chemical state of Eu3+ ions in fluoridated hydroxyapatite. The results of these experiments indicated that the samples with a different fluorine substitution ratio were prepared successfully by maintaining the apatite structure. With an increasing fluorine substitution ratio, the morphology maintained a rod-like structure but the aspect ratio tended to decrease. XPS patterns displayed that the fluorine replaced the hydroxyl group and brought environmental variation. The fluorine ions could affect the crystal field environment and promote luminescence conversion. There was a linear relationship between the fluorine substitution ratio and luminescence enhancement.

Impact of Dopants on the Electrical and Optical Properties of Hydroxyapatite

“…In the case of cerium-doped HAp, the luminescence quenching occurred between the nearest cerium ions in the matrix as reported by Kolesnikov et al [48]. Various fluoridated HAp doped with Eu 3+ ion nanoparticles were prepared by hydrothermal technique and the fluorine ions could influence the crystal field environment for luminescence conversion [49]. Reddy et al observed a strong green emission from Ni 2+ -doped Ca-Li HAp (CLHA) [50].…”

Strontium Phosphate Composite Designed to Red-Emission at Different Temperatures

“…Apatite (Ap) is a large family of compounds commonly occurring in nature. Calcium hydroxyapatite (Ca 10 (PO 4 )6(OH) 2 – CaHAp) is ideal representative of this family of minerals, which can be easily doped with different kinds of ions [ 1 , 2 ]. Apatite is applied in plenty industrial fields as catalysts, laser hosts, luminescent materials, gas sensors, ionic conductors and adsorbents [ 3 , 4 ].…”

Rare Earths Doped Materials

“…All publications in this Special Issue are original contributions. Different materials doped with Rare Earth Elements are presented in the publications, among them nanoparticles of Zr 1-x Eu x O 2-0.5x [1], fluoridated hydroxyapatite [2], Bi 12 GeO 20 sillenite bulk crystals [3], GdSb 2 O 4 Br, TbSb 2 O 4 Br [4], and LuVO 4 [5].…”

“…The influence of a Rare Earth Element on luminescence properties is demonstrated by Eu 3+ -doped fluoridated hydroxyapatite. The relationship between the luminescence enhancement of Eu 3+ ions and the fluorine substitution ratio for hydroxyl groups in hydroxyapatite was discussed by Zhang et al [2]. The effects of the substitution of hydroxyl groups by fluorine on the phase composition, crystallinity, and crystal size were studied.…”

“…The effects of the substitution of hydroxyl groups by fluorine on the phase composition, crystallinity, and crystal size were studied. It was found that fluorine affects the symmetry of the structure and thus changes the surrounding environment of the Eu 3+ ions [2].…”