Construction of hybrid material with double chemical bond from functional bridge ligand: Molecular modification, lotus root-like micromorphology and strong luminescence

Modifying benzoic acid with a cross-linking molecule (3-aminopropyl)triethoxysilane (abbreviated as APES), a fictional molecular bridge with double reactivity was achieved by the amidation reaction between them. Then the modified functional molecule, which behaving as a bridge, both coordinate with terbium ion through amide’s oxygen atom and form the Si–O chemical bond in an in situ sol–gel process with matrix precursor (tetraethoxysilane, TEOS). As a result, a novel molecular hybrid material (Tb-BA-APES) with double chemical bond (Tb–O coordination bond and Si–O covalent bond) was constructed. The strong luminescence of Tb3+ substantiates optimum energy couple and effective intramolecular energy transfer between the triplet state energy of modified ligand bridge and emissive energy level of Tb3+. Especially SEM of the molecular hybrid material exhibits unexpected microlotus root-like pore morphology.