Cichocka Nikola, Kaszewski Jaroslaw, Matus Krzysztof, Reszka Anna, Minikayev Roman, Wszelaka-Rylik Malgorzata, Kaminska Agata
Cardinal Stefan Wyszynski University, Faculty of Mathematics and Natural Sciences, School of Exact Sciences, Institute of Physical Sciences, Dewajtis 5, PL-01815 Warsaw, Poland.
Institute of Physics Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668 Warsaw, Poland.
Nanotechnology. 2025 Jun 23;36(26). doi: 10.1088/1361-6528/ade0c4.
In this study, we investigated the impact of growth conditions on the structural and optical properties of yttrium/aluminum-based oxide powders doped with Eusynthesized via microwave-driven hydrothermal method. The effects of the starting material composition (Y/Al molar ratio) and the pH value of the reaction medium on the phase composition, morphology, and luminescent properties of the Eu dopant in the obtained powders were analyzed. Detailed structural and optical characterization of material was performed using x-ray diffraction, scanning and transmission electron microscopy (SEM, TEM), and the results were confronted with the analysis of the photoluminescence (PL), PL decay kinetics, and PL excitation spectroscopy features, as the Eu dopant apart of being efficient red phosphor is also known as a good crystal symmetry probe. It has been shown that the pH value of the reaction mixture and the Y/Al molar ratio significantly affect the phase composition of the powders, morphology, size, and consequently, the intensity of emission peaks and decay times. Despite using the yttrium to aluminum ratios of 1:1 in one of the sample series, corresponding to YAlOperovskite, the presence of two other phases: yttrium aluminum garnet (YAlO, YAG) and yttrium oxide (YO) in different proportions was observed. Additionally, TEM images demonstrated the presence of a non-crystalline phase in two samples which correlated with a significant broadening of PL lines. The analysis of the CIE diagrams revealed that a decrease in pH value causes the an increase of the red component of the obtained powder phosphor emission. The research provides new insights into the relationships between synthesis parameters and the physicochemical and optical properties of Eu-doped yttrium/aluminum-based oxide materials compounds, which is important for both optimizing the growth parameters to obtain desired Y-Al-O powder crystal phase and for the use of these powders in applications as phosphor materials.
在本研究中，我们研究了生长条件对通过微波驱动水热法合成的掺铕钇/铝基氧化物粉末的结构和光学性质的影响。分析了起始原料组成（Y/Al摩尔比）和反应介质的pH值对所得粉末中Eu掺杂剂的相组成、形态和发光性质的影响。使用X射线衍射、扫描和透射电子显微镜（SEM、TEM）对材料进行了详细的结构和光学表征，并将结果与光致发光（PL）、PL衰减动力学和PL激发光谱特征分析进行了对比，因为Eu掺杂剂除了是一种高效的红色磷光体外，还被认为是一种良好的晶体对称性探针。结果表明，反应混合物的pH值和Y/Al摩尔比显著影响粉末的相组成、形态、尺寸，进而影响发射峰强度和衰减时间。尽管在一个样品系列中使用了1:1的钇铝比，对应于YAlO钙钛矿，但观察到另外两个相的存在：不同比例的钇铝石榴石（YAlO，YAG）和氧化钇（YO）。此外，TEM图像显示两个样品中存在非晶相，这与PL线的显著展宽相关。CIE图分析表明，pH值的降低导致所得粉末磷光体发射的红色成分增加。该研究为合成参数与掺Eu钇/铝基氧化物材料化合物的物理化学和光学性质之间的关系提供了新的见解，这对于优化生长参数以获得所需的Y-Al-O粉末晶相以及将这些粉末用作磷光体材料的应用都很重要。
