Preparation and cathodoluminescence characteristics of rare earth activated BaAl2O4 phosphors. (September 2018)

• Record Type: Journal Article
• Authors: Benourdja, S.; Kaynar, Ümit H.; Ayvacikli, M.; Karabulut, Y.; Guinea, J. Garcia; Canimoglu, A.; Chahed, L.; Can, N.
• Is Part Of: Applied radiation and isotopes. Volume 139(2018:Sep.)
• Page Start: 34
• Page End: 39
• Publication Date: 2018-09
• Subjects: BaAl2O4 -- Rare earths -- XRD -- Cathodoluminescence; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2018.04.023
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: Undoped and Pr, Sm and Tb activated BaAl2 O4 phosphors have been synthesized by solid state reaction method and combustion method. The structure and morphological observation of the phosphor samples were monitored by X-ray powder diffraction (XRD) and environmental scanning electron microscope (ESEM) coupled to an energy dispersive X-ray spectrometer (EDS). The all diffraction peaks are well assigned to standard data card (PDF♯17–306). Emission properties of the samples were explored using light emission induced by an electron beam (i.e cathodoluminescence, CL) at room temperature (RT). Undoped BaAl2 O4 sample exhibits a broad defect emission from 300 to 500 nm from the aluminate defect centres. CL spectra recorded at room temperature display that the as-prepared BaAl2 O4 :Ln (Ln=Pr, Sm and Tb) phosphors exhibit different luminescence colors coming from different rare earth activator ions. The transition 4 G5/2 → 6 H7/2 located at 606 and 610 nm for Sm 3+ can occur as hypersensitive transition having the selection rule Δ J = ± 1. For the Tb 3+ doped samples, they exhibit D 4 5 green line emissions. The proposed luminescent mechanisms of all doped rare earth ions are also discussed. Highlights: Sm, Tb and Pr activated BaAl2 O4 phosphors were successfully synthesized by solid state reaction and combustion method. The luminescence properties were studied by electron beam excitation. The proposed luminescent mechanisms of all doped rare earth ions are also discussed.