Luminescence characteristics of O⁶⁺ ion beam and γ-ray irradiated Ca₉La(PO₄)₅(SiO₄)F₂:Eu phosphor

Fluorapatite Ca₉La(PO₄)₅(SiO₄)F₂: Eu with variable molar concentrations of Eu³⁺ (0.05–1.0 mol%) were synthesised by the solid-state reaction method and their photoluminescence (PL), thermoluminescence (TL) characteristics were studied after irradiating the samples with γ-rays and 75 MeV O⁶⁺ ion beam. The formation of the material was confirmed using X-ray diffraction pattern followed by Scanning electron microscopy and Fourier transform infra-red (FTIR) spectrum. The morphology of the synthesised powder was observed to be polycrystalline constituted by microcrystalline particles. FTIR spectrum shows characteristic bands, 563 cm⁻¹ for bending vibration υ₄ and 1035 cm⁻¹ for stretching vibration υ₃. PL spectra show absorption bands at 395 and 466 nm corresponding to ⁷F₀→⁵L₆ and ⁷F₀→⁵D₂ transitions and the emission band was seen at around 595 and 616 nm describing ⁵D₀→⁷F_j transitions (j = 1,2). Furthermore, TL glow curves of both γ-rays and 75 MeV O⁶⁺ ion beam irradiated samples show a prominent peak at around 145°C with a small hump at around 245°C. The concentration 0.2 and 1 mol% was found to be the best concentration for studying TL properties of Ca₉La(PO₄)₅(SiO₄)F₂: Eu irradiated with γ-rays and 75 MeV O⁶⁺ ion-beam respectively.