Biphenylene-bridged mesostructured organosilica as a novel hybrid host material for Ln~(III) (Ln = Eu, Gd, Tb, Er, Yb) ions in the presence of 2-thenoyltrifluoroacetone

摘要

A hierarchically ordered 4,4'-biphenylene-bridged mesoporous organosilica framework (Bp-PMO) has been synthesized with the aim of using it as a new hybrid host for Ln~(III) ions. A series of novel organic-inorganic luminescent hybrid materials have been obtained by covalently linking Ln~(III) complexes (Ln .= Eu, Gd, Tb, Er, and Yb) to Bp-PMO functionalized with 2-thenoyltrifluoroacetone (HTTA). The visible and NIR photoluminescence studies of the hybrid materials show that Bp-PMO acts both as an inorganic host and an organic co-sensitizer for Ln~(III) ions. The intrinsic quantum yield and lifetime data obtained for the hybrid material containing Eu~(III) (54.5% and 615 μs) are among the highest values reported for hybrid materials containing Eu~(III)tetrakis(|3-diketonate) complexes. The combination of Bp-PMO and HTTA also provides sizable sensitization for Tb~(III), Er~(III)and Yb~(III) ions. The overall quantum yields and lifetime measurements for mixed metallic hybrid materials show that Ln → Ln' energy transfer occurs in the mixed ianthanide systems. In addition, controlling the Ln/Ln' ratio allows one to tune the emission colour.