Phosphors with the compositions of Ca2−xEuxMgSi2O7 (x = 0.005, 0.015, 0.025, 0.035, and 0.045) are synthesized in a reduction atmosphere (5% H₂ + 95% N₂) using a solid-state reaction method. At first, the Ca1.975Eu0.025MgSi2O7 powder is synthesized at 1350∘C with a duration of 1 ∼ 6 h to find the optimum synthesizing time. SEM images show that the particle sizes increase with synthesizing time and as the synthesizing time is more than 4 h, the abnormal particles appear and the intensities at the emission peaks of photoluminescence excitation (PLE) and photoluminescence emission (PL) spectra decrease. Next, 1350∘C and 4 h are used as synthesized parameters, which are used to find the concentration quench effect of Ca2−xEuxMgSi2O7 phosphors. As the concentration of Eu2+ ions of Ca2−xEuxMgSi2O7 phosphors increases, the intensities at the emission peaks of PLE and PL spectra first increase and reach the maximum values at x = 0.025, and then they decrease as the concentration of Eu2+ ions further increases. These results prove that the synthesizing time and concentration of Eu2+ ions are two important factors to affect the photoluminescence properties of Ca2−xEuxMgSi2O7 phosphors.

中文翻译：

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合成时间和 Eu2+ 浓度对 Ca2−xEuxMgSi2O7 荧光粉光致发光性能的影响

荧光粉的组成钙2-X欧盟X镁硅2○7(X = 0.005, 0.015, 0.025, 0.035 和 0.045) 是在还原气氛 (5% H ₂ + 95% N ₂ ) 中使用固态反应方法合成的。起初，钙1.975欧盟0.025镁硅2○7粉末在1350合成∘C 持续时间为1 ～ 6h 找到最佳合成时间。SEM图像显示，随着合成时间的延长，粒径增大，合成时间超过4 h时，出现异常颗粒，光致发光激发（PLE）和光致发光（PL）光谱的发射峰强度降低。接下来，1350∘以 C 和 4 h 为合成参数，用于寻找浓度猝灭效应钙2-X欧盟X镁硅2○7荧光粉。作为浓度欧盟2+的离子钙2-X欧盟X镁硅2○7荧光粉增加，PLE 和 PL 光谱的发射峰处的强度首先增加并达到最大值X = 0.025, 然后随着浓度的增加而减少欧盟2+离子进一步增加。这些结果证明了合成时间和浓度欧盟2+离子是影响光致发光特性的两个重要因素钙2-X欧盟X镁硅2○7荧光粉。