Work

Ultrafast Photoinduced Electron Transfer Between Donor (Eosin‐Y) and Acceptor (Naphthoquinone) in a Supramolecular Array Based on a Coordination Cage Host

Year: 2025

Type: article

Abstract: An octanuclear M8L12 coordination cage host (HPEG ⋅ M) in aqueous solution binds neutral electron‐accepting guests such as naphthoquinone (NQ) in its central cavity via the hydrophobic effect, and multiple anionic photosensitisers such as Eosin‐Y (EY2−) around the exterior surface due to 16+ charge on the complex cation: this is confirmed by both solution titration experiments and X‐ray crystallography. In the three‐component assembly HPEG ⋅ Cd/EY2−/NQ, photoexcitation of EY2− at 525 nm results in ultrafast (ca. 1 ps) photoinduced EY2−→NQ electron transfer from surface‐bound EY2− to cavity‐bound NQ (which have been brought into close proximity by their interactions with different sites on the host cage) to give the charge‐separated pair EY⋅−/NQ⋅−, identified by transient absorption spectroscopy: back‐ET results in charge recombination in ≈70 ps. The assembly of donor and acceptor components via orthogonal interactions using the host cage as a scaffold presents a promising route into spatial control of multiple components in supramolecular arrays for photophysical applications.

Source: Chemistry - A European Journal

DOI: 10.1002/chem.202404647

Authors: Max B. Tipping, Jack M. Woolley, James R. Williams, Michael D. Ward

Institution: University of Warwick

Language: English

Topic: Supramolecular Chemistry and Complexes

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: bronze

Funders: Leverhulme Trust, University of Warwick

Award: G7234731058