Features of Luminescence of Hydroxyapatite Ca5–xOH(PO4)3:Eu3+ Co-Doped with Dy3+, Y3+ and B3+ Ions

Ca5 – xOH(PO4)3 hydroxyapatite (HAP) is doped using dysprosium Dy3+ and europium Eu3+ ions to explore the effect of co-doping by Dy3+, Y3+ and B3+ ions on the luminescent properties of HAP:Eu. The doping involves high-temperature HAP annealing in presence of corresponding Dy2O3, Eu2O3, Y2O3 oxides and boric acid (H3BO3). The photoluminescence spectra of doped HAP:Eu and co-doped HAP:Eu, Dy, HAP:Eu, B, HAP:Eu, Y hydroxyapatites are investigated. The continuous laser radiation at the wavelength λ = 405 nm is used to excite photoluminescence. The peculiarities of the change in the photoluminescence spectrum of HAP:Eu after co-doping with Dy3+, B3+, and Y3+ ions are registered. When co-doped using Dy3+ ions the HAP:Eu, Dy spectrum consists of narrow spectral peaks corresponding to Dy3+ and Eu3+ ions in the HAP matrix. When B3+, Y3+ ions are used for co-doping a dramatic change in the photoluminescence spectra develops: a broad and intense photoluminescence band appears in the HAP:Eu, B and HAP:Eu, Y spectra with the maximum detected at λ = 515 nm and λ = 520 nm, respectively. Co-doping HAP:Dy with B3+, Y3+ ions practically does not result in changing the photoluminescence spectrum of HAP:Dy consisting of narrow spectral peaks corresponding to Dy3+ ions in the HAP matrix.