Institute of Experimental Physics, University of Gdańsk, Wita Stwosza 57, 80-952 Gdańsk, Poland.
J Phys Condens Matter. 2013 Oct 23;25(42):425501. doi: 10.1088/0953-8984/25/42/425501. Epub 2013 Sep 27.
In this contribution, the photoluminescence, time-resolved luminescence and luminescence kinetics of α'-Sr2SiO4:Eu(2+) are studied. The luminescence of Sr2SiO4:Eu(2+) consists of two broad bands, peaked at 490 nm (blue-green) and 570 nm (yellow-orange), which originate from two luminescence centers, related to Eu(2+) in ten-coordinated SI and nine-coordinated SII sites, respectively. Based on spectroscopic data the energetic structure of Sr2SiO4:Eu(2+) has been developed, which includes the bands edges, energies of Eu(2+) in the SI and SII sites and energies of strontium and oxygen vacancies. To investigate the long-lasting luminescence phenomenon in Sr2SiO4:Eu(2+) the temperature influence on the time evolution of luminescence was analyzed. It has been found that the long-lasting luminescence is related to the Eu(2+) in SII site. The shallowest traps responsible for emission decaying within a few seconds are tentatively attributed to the [Eu(3+)(SII)-[Formula: see text]] centers. The depth of traps responsible for the long-lasting luminescence observed at room temperature has been estimated as equal 0.73 eV.
在本研究中，我们对α'-Sr2SiO4:Eu(2+)的荧光、时间分辨荧光和荧光动力学进行了研究。Sr2SiO4:Eu(2+)的荧光由两个宽带组成，分别位于 490nm（蓝绿色）和 570nm（黄橙色），它们分别来源于与 Eu(2+)在十配位 SI 和九配位 SII 位相关的两个发光中心。基于光谱数据，我们构建了 Sr2SiO4:Eu(2+)的能态结构，其中包括能带边缘、SI 和 SII 位 Eu(2+)的能量以及锶和氧空位的能量。为了研究 Sr2SiO4:Eu(2+)中的长余辉发光现象，我们分析了温度对荧光时间演化的影响。结果表明，长余辉发光与 SII 位的 Eu(2+)有关。发射衰减在几秒钟内的最浅陷阱被暂时归因于[Eu(3+)(SII)-[公式：见正文]]中心。在室温下观察到的长余辉发光的陷阱深度估计为 0.73eV。
