Studies on terbium doped apatite phosphors prepared by precipitation under microwave conditions
| Autor: | Laura Muresan, I. Perhaita, Gheorghe Borodi, Doina Prodan |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Mechanical Engineering Doping Metals and Alloys Analytical chemistry chemistry.chemical_element Terbium Phosphor 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Apatite 0104 chemical sciences chemistry Mechanics of Materials visual_art Activator (phosphor) Materials Chemistry visual_art.visual_art_medium Crystallite Fourier transform infrared spectroscopy 0210 nano-technology Luminescence |
| Zdroj: | Journal of Alloys and Compounds. 755:135-146 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2018.04.274 |
| Popis: | In this study we present our first attempts to obtain silicate apatite phosphors by precipitation with NaOH under microwave conditions. Y and La precursors fired at different temperatures (800 °C÷1400 °C) led to phosphors with hexagonal apatite structure belonging to the space group P63/m and with crystallites size up to 105 nm. The structure and chemical composition of samples were evaluated based on FTIR, XRD and ICP-OES while the morphology, surface state and porosity were revealed using SEM and BET investigations. The impact of the firing temperature on the purity phase, crystalline order degree, crystallites size and luminescent properties of the apatite phosphors are discussed. It was found that the nature of rare earth (Y3+ or La3+) same as the incorporation degree of activator (Tb3+) is responsible for the apatites green - turquoise emission. ICP-OES measurements show that the Tb3+ amount incorporated in the apatite lattice increase with firing temperature and is lower in La-phosphors compared with Y-phosphors. The 5D4–7F5 transition observed in the green spectral domain was dominant in Y- phosphors while 5D3-7F6,5,4 transitions from blue spectral region was dominant in La-phosphors. The chromatic coordinates shifts from green to turquoise with firing temperature and depends on the excitation radiation, indicating the applicative potential of these phosphors in display screens for solid-state lighting applications. |
| Databáze: | OpenAIRE |
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