Two photoactive lanthanide (Eu3+, Tb3+) hybrid materials of modified beta-diketone bridge directly covalently bonded mesoporous host (MCM-41)

Abstract

In this context, two beta-diketone ligands, dibenzoylmethane (DBM) and acetylacetone (ACAC) were modified with 3-(triethylsilyl)-propylisocyanate (TEPIC) through the extraction of hydrogen of ethylene groups. Then Eu3+ and Tb3+ complexes with the two modified ligands (DBM-Si and ACAC-Si) were fabricated to mesoporous host (MCM-41) by template-directed co-condensation of tetraethyl orthosilicate, resulting in two kinds of novel covalently bonded hybrid materials (denoted as DBM-MCM-41 and ACAC-MCM-41). XRD, N-2 adsorption/desorption and SEM reveal that the two covalently bonded hybrid materials have high surface area, uniform mesopore structure and good crystallinity. Especially the luminescent properties present that the modified dibenzoylmethane (DBM-Si) could sensitize Eu(III) ions to exhibit red luminescence and the modified acetylacetone (ACAC-Si) could sensitize Tb(III) ions to exhibit green luminescence, respectively. The hybrid materials covalently bonded MCM-41 possess the higher intensities and longer lifetimes than those of pure complexes (Eu-DBM and Tb-ACAC). (C) 2007 Elsevier B.V. All rights reserved.