Inorganic scintillation crystals have been widely used in applications of high-energy physics, nuclear medical imaging, industrial nondestructive inspection, etc. In this work, a single crystal Ba3Y(PO4)3(BYP) with 1.0 at% Ce3+-doping concentration was first grown by the Czochralski method, and the electronic structure was calculated using first principles based on density functional theory. In addition, a series of Ce3+-doped BYP phosphors were synthesized, and the fluorescence emission under UV excitation was measured through low-temperature spectroscopy, containing double-peaked emission from 5d–4f transition and self-trapped exciton recombination. A comparison of the UV and X-ray-excited fluorescence spectra reveals the existence of oxygen vacancies as well as F+ centers in the crystal. The air annealing of the crystal effectively reduces the thermoluminescence defects but reduces the emission intensity under UV or X-ray excitation. The BYP:Ce crystal shows a fast decay lifetime of 15.5 ns, and the fast component is as short as 8 ns. The results show that the Ce3+-doped BYP crystal has potential as a kind of scintillator with fast decay properties.
This research focuses on the fluorescent powder materials based on a single matrix of this type of LED. Taking Ba2CaWO6 as an example, mixing Dy3+ alone can produce blue and white light at 318nm UV excitation. At the same time, mixing Dy3+
with Eu3+ can make the fluorescent powders realize the emission of 491 nm/577 nm of Dy3+ and 588 nm of Eu3+. Dy3+ is set to 0.06 and the ratio of Eu3+ is adjusted to make the luminous color gradually close to white. In the study of Ba3Y(PO4)3
· xDy3+ · yEu3+, x is set as 0.07, and the content of y is set as 0.01∼0.08. Dy3+ alone will emit blue and white light under the laser at 391 nm. By increasing the content of Eu3+, polychromatic emission
can be carried out, and white light can be obtained by adjusting the concentration of Eu3+. At the same time, the application functions of white LED packaging are tested for the above materials. The results show that both Ba2CaWO6 · xDy3+
· yEu3+ and Ba3Y(PO4)3 · xDy3+ · yEu3+ materials can realize white lighting by adjusting the ratio of Eu3+ · Dy3+, increasing the proportion of Eu3+
can improve the color rendering of white LED.
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