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采用微波水热法合成不同孔径的介孔分子筛(mesoporous molecular sieve,MCM-41),通过Pechini溶胶-凝胶法合成Eu-MCM-41,并将EuPO4:Zn晶体沉积在MCM-41表面,研究介孔材料孔径对荧光强度的影响。结果表明:EuPO4:Zn无荧光,Eu-MCM-41发出很强的蓝光(468nm)和橙光(593nm);当EuPO4:Zn颗粒的孔径小于3.1nm时,荧光强度随孔径的增大而增加,大于3.1nm时,则相反。影响铕离子(Ⅲ)的发光强度主要有量子点的密度、铕离子中心的分裂和量子点的集聚程度,并且都与MCM-41的孔径有关,在改变选择规则的同时也影响磁偶极子,尤其使得f→f转换的量子跃迁成为可能。
Mesoporous molecular sieves (MCM-41) with different pore sizes were synthesized by microwave hydrothermal method. Eu-MCM-41 was synthesized by Pechini sol-gel method and EuPO4: Zn crystals were deposited on the surface of MCM-41. Influence of pore size of mesoporous materials on fluorescence intensity. The results show that EuPO4: Zn has no fluorescence, Eu-MCM-41 emits strong blue light (468nm) and orange light (593nm). When the aperture of EuPO4: Zn particles is less than 3.1nm, the fluorescence intensity increases with the increase of aperture , When it is larger than 3.1nm, the opposite is true. The luminescence intensity affecting the europium ions (III) are mainly the density of quantum dots, the splitting of the center of europium ions and the concentration of quantum dots, all of which are related to the pore size of MCM-41. The changes of selection rules also affect the magnetic dipole , In particular, makes the quantum transition of f → f conversion possible.