Improved luminescence properties of europium complexes encapsulated into mesoporous SBA-15

Two kinds of Eu3+ COmplexes-Eu(TTA)3(TPPO)2 (TTA: thenoyltrifluoroacetone, TPPO: triphenylphosphineoxide) and Eu(BA)3(TPPO)2 (BA: 1-benzoylacetone)-were fully encapsulated, uniformly distributed into the channels of unmodified and modified SBA-15, and structurally characterized. The luminescent properties of the encapsulated complexes were systematically studied in contrast to the pure complexes. The results indicate that the excitation bands assigned to the pi-pi* electron transition of the ligands for Eu3+ complexes encapsulated in SBA-15 were split into different components, and the 5D0-7F0 transitions became partly allowed. The emission lines for the 5D0-7F2 transitions became broader and the relative intensity for different crystal field components varied greatly in comparison to the pure complex. Most importantly, the photostability and thermostability of the emissions improved considerably.