title: Enhancing the luminescence of Eu3+/Eu2+ion-doped hydroxyapatite by fluoridation and thermal annealing.
abstract: This paper reports a novel way for the synthesis of a europium (Eu)-doped fluor-hydroxyapatite (FHA) nanostructure to control the luminescence of hydroxyapatite nanophosphor, particularly, by applying optimum fluorine concentrations, annealed temperatures and pH value. The Eu-doped FHA was made using the co-precipitation method followed by thermal annealing in air and reducing in a H2atmosphere to control the visible light emission center of the nanophosphors. The intensities of the OH-group decreased with the increasing fluorine concentrations. For the specimens annealed in air, the light emission center of the nanophosphor was 615 nm, which was emission from the Eu3+ion. However, when they were annealed in reduced gas (Ar + 5% H2), a 448 nm light emission center from the Eu2+ion of FHA was observed. The presence of fluorine in Eu-doped FHA resulted in a significant enhancement of nanophosphor luminescence, which has potential application in light emission and nanomedicine.
authors.affiliation: Advanced Institute for Science and Technology (AIST), Hanoi University of Science and Technology (HUST), No. 01, Dai Co Viet Road, Hanoi, Vietnam.
authors.forename: Hoang Nhu
authors.initials: HN
authors.lastname: Van
authors.affiliation: Advanced Institute for Science and Technology (AIST), Hanoi University of Science and Technology (HUST), No. 01, Dai Co Viet Road, Hanoi, Vietnam.
authors.forename: Phuong Dinh
authors.initials: PD
authors.lastname: Tam
authors.affiliation: Advanced Institute for Science and Technology (AIST), Hanoi University of Science and Technology (HUST), No. 01, Dai Co Viet Road, Hanoi, Vietnam.
authors.forename: Nguyen Duc Trung
authors.initials: NDT
authors.lastname: Kien
authors.affiliation: Advanced Institute for Science and Technology (AIST), Hanoi University of Science and Technology (HUST), No. 01, Dai Co Viet Road, Hanoi, Vietnam.
authors.forename: Pham Thanh
authors.initials: PT
authors.lastname: Huy
authors.affiliation: Advanced Institute for Science and Technology (AIST), Hanoi University of Science and Technology (HUST), No. 01, Dai Co Viet Road, Hanoi, Vietnam.
authors.forename: Vuong-Hung
authors.initials: VH
authors.lastname: Pham
mesh_terms: D017886:Durapatite / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D005457:Fluoridation; D006863:Hydrogen-Ion Concentration; D006882:Hydroxyapatites / Q000737:chemistry; D008027:Light; D049408:Luminescent Agents / Q000138:chemical synthesis / Q000737:chemistry*; D008163:Luminescent Measurements; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D006882:Hydroxyapatites; D049408:Luminescent Agents; D005063:Europium; C028869:fluor-hydroxylapatite; D017886:Durapatite
keywords: europium; hydroxyapatite; luminescence; nanobiophosphors; nanophosphors