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通过微波辅助水热法合成MCM-41介孔材料,经溶胶凝胶组装过程将EuPO4∶Zn分散到MCM-41表面上和孔道中,制备成以MCM-41为基质的复合发光材料EuPO4∶Zn@MCM-41粉末。通过XRD、FTIR、氮吸附、SEM、HRTEM、EDS对该材料进行了表征,用单因素法探究了原料配比(Eu(NO3)3、Zn(NO3)2的加入量和反应条件(煅烧的温度、时间)对EuPO4∶Zn@MCM-41在593 nm处发光强度的影响,并研究其影响机理。荧光分析发现,EuPO4∶Zn基本不发射荧光,而EuPO4∶Zn@MCM-41材料具有蓝光段和红光段的荧光发射,主要发光带以468和593 nm为中心。593 nm处的发射归因于Eu3+的4f组内5D0→7F1跃迁,即Eu3+中心离子所在晶格格位对称性决定的磁偶极跃迁。研究表明以MCM-41为载体,能够大大降低颗粒的团聚程度,并使EuPO4:Zn颗粒具有更小的粒径;同时EuPO4∶Zn@MCM-41中Eu3+发光中心具有更大的裂分,MCM-41的纳米孔道使Eu3+的发光中心分离,降低了Eu3+之间电子云之间的重叠,大大减小了荧光的猝灭,因此MCM-41能有效降低Eu3+复合物荧光猝灭。
MCM-41 mesoporous materials were synthesized by microwave assisted hydrothermal method. EuPO4:Zn was dispersed on the surface of MCM-41 and in the pores by sol-gel assembly process to prepare the composite luminescent material EuPO4:Zn @ MCM-41 powder. The material was characterized by XRD, FTIR, nitrogen adsorption, SEM, HRTEM and EDS. The content of Eu (NO3) 3, Zn (NO3) 2 and the reaction conditions Temperature and time) on the luminescence intensity of EuPO4:Zn @ MCM-41 at 593 nm and the mechanism of its effect were studied.Fluorescence analysis showed that EuPO4:Zn did not emit fluorescence basically, while the EuPO4:Zn @ MCM-41 material had blue light The emission bands at 593 nm are attributed to the 5D0 → 7F1 transitions within the 4f group of Eu3 +, ie, the lattice symmetry of the Eu3 + central ion is determined Magnetic dipole transition.The results show that MCM-41 can greatly reduce the agglomeration degree of particles and make EuPO4: Zn particles have smaller particle size, meanwhile the Eu3 + luminescence centers in EuPO4: Zn @ MCM-41 have larger , MCM-41 nanopore separation of Eu3 + luminescent center, reducing the electron cloud between Eu3 + overlap, greatly reducing the fluorescence quenching, so MCM-41 can effectively reduce fluorescence quenching of Eu3 + complexes Off