Encapsulating a Ternary Europium Complex in a Silica/Polymer Hybrid Matrix for High Performance Luminescence Application

The sol−gel method has been proven to be an excellent approach for the preparation of hybrid materials. Combining luminescent lanthanide complexes with silica/polymer hybrid materials to improve the stability and even to increase luminescent properties is fascinating and promising in the lanthanide complex hybrid material field. A series of tough and transparent hybrid materials polymer−Eu−L−P gel have been assembled by a ternary europium complex [Eu2L2(Phen)2(CH3OH)4]Cl2·(CH3OH)6(H2L = 2,2′-(((2,4,6-trimethyl-1,3-phenylene)bis(methylene))bis(oxy))dibenzoic acid, Phen =1,10-phenanthroline) embedded into microporous silica/polymer [poly(methyl methacrylate) (PMMA), polyvinylpyrrolidone (PVP), and poly(vinyl butyral) (PVB)] matrixes. The Fourier transform infrared (FTIR) spectra, UV−vis absorption spectra, X-ray diffraction (XRD), scanning electronic microstructure (SEM), thermogravimetry (TG), and luminescent properties of the europium ternary complex and the hybrid materials (Eu−L−P gel and polymer−Eu−L−P gel) are described in detail. The hybrid materials polymer−Eu−L−P gel display more efficient unit mass luminescence emission, longer lifetime, higher quantum efficiency, greater thermal stability, and better exposure durability in comparison with the Eu−L−P gel. The result may support the conclusion that the polymers could interact with the complex, act as antennae, and transfer energy to the central Eu3+ ions. Comparatively, diminutive distinction exists in the hybrid materials containing different polymers originated from the weak interactions between the host and the guest.溶胶-凝胶法（sol−gel method）已被证实是制备杂化材料（hybrid materials）的优异途径。将发光镧系配合物（luminescent lanthanide complexes）与二氧化硅/聚合物杂化材料相结合，以提升其稳定性甚至优化发光性能，在镧系配合物杂化材料领域极具吸引力与应用前景。本研究通过将三元铕配合物[Eu₂L₂(Phen)₂(CH₃OH)₄]Cl₂·(CH₃OH)₆（其中H₂L = 2,2′-(((2,4,6-三甲基-1,3-亚苯基)双(亚甲基))双(氧基))二苯甲酸，Phen = 1,10-菲咯啉）嵌入微孔二氧化硅/聚合物[聚甲基丙烯酸甲酯（poly(methyl methacrylate), PMMA）、聚乙烯吡咯烷酮（polyvinylpyrrolidone, PVP）及聚乙烯醇缩丁醛（poly(vinyl butyral), PVB）]基体中，成功制备得到一系列坚韧透明的聚合物-Eu-L-P凝胶杂化材料。本研究对该三元铕配合物，以及Eu-L-P凝胶、聚合物-Eu-L-P凝胶杂化材料的傅里叶变换红外（FTIR）光谱、紫外-可见吸收光谱、X射线衍射（XRD）、扫描电子显微形貌（SEM）、热重（TG）分析及发光性能进行了详细表征。相较于纯Eu-L-P凝胶，聚合物-Eu-L-P凝胶杂化材料展现出更优异的单位质量发光强度、更长的荧光寿命、更高的量子效率、更佳的热稳定性以及更出色的曝光耐久性。该研究结果佐证了“聚合物可与配合物相互作用，充当天线基团并将能量传递至中心Eu³+离子”这一推论。相较而言，由于基体与客体之间的相互作用较弱，采用不同聚合物制备的杂化材料之间仅存在微小的性能差异。