Tailoring the Solid-State Fluorescence of BODIPY by Supramolecular Assembly with Polyoxometalates.

A cationic boron dipyrromethene (BODIPY) derivative () has been successfully combined with two polyoxometalates (POMs), the Lindqvist-type [WO] and the β-[MoO] units, into three new supramolecular fluorescent materials , , and . The resulting hybrid compounds have been fully characterized by a combination of single-crystal X-ray diffraction, IR and UV-vis spectroscopies, and photoluminescence analyses. This self-assembly approach prevents any π-π stacking interactions not only between the BODIPY units, responsible for aggregation-caused quenching (ACQ) effects, but also between the BODIPY and the POMs, avoiding intermolecular charge-transfer effects.

New Robust Luminescent Supramolecular Assemblies Based on [Ln(MoO)] (Ln = Eu, Sm) Polyoxometalates.

This work highlights for the first time the photoluminescence (PL) properties of two new [Ln(MoO)] (Ln = Eu, Sm) lanthanide-containing polyoxometalates. Stable crystals of their tetrabutylammonium salts were synthesized, and their structures were confirmed by single-crystal X-ray diffraction. The robustness of the [Ln(MoO)] complexes in an acetonitrile solution has been evidenced by Fourier transform Raman and PL spectroscopies.

Strong Solid-state Luminescence Enhancement in Supramolecular Assemblies of Polyoxometalate and "Aggregation-Induced Emission"-active Phospholium.

Two new supramolecular fluorescent hybrid materials, combining for the first time [M O ] (M=Mo, W) polyoxometalates (POMs) and aggregation-induced emission (AIE)-active 1-methyl-1,2,3,4,5-pentaphenyl-phospholium (1 ), were successfully synthesized. This novel molecular self-assembling strategy allows designing efficient solid-state emitters, such as (1) [W O ], by directing favorably the balance between the AIE and aggregation-caused quenching (ACQ) effects using both anion-π and H-bonding interactions in the solid state. Combined single-crystal X-ray diffraction, Raman, UV-vis and photoluminescence analyses highlighted that the nucleophilic oxygen-enriched POM surfaces strengthened the rigidity of the phospholium via strong C-H⋅⋅⋅O contacts, thereby exalting its solid-state luminescence.