# Aroyl-S,N-ketene acetal-triarylamine bichromophores – intramolecular energy transfer and dual emission upon induced aggregation and encapsulation

## TL;DR

This paper explores how a specific type of bichromophore emits light differently when aggregated or encapsulated, revealing new insights into energy transfer and emission behavior.

## Contribution

The study introduces a new class of bichromophores with controllable dual emission through substitution patterns and aggregation.

## Key findings

- Bichromophores exhibit aggregation-induced dual emission (AIDE) controlled by substitution patterns.
- Encapsulation in polystyrene nanoparticles significantly increases fluorescence quantum yield.
- Intramolecular energy transfer efficiency is modulated by the dye substitution pattern.

## Abstract

Aroyl-S,N-ketene acetal-based bichromophores are synthesized by a catalytic aryl amination and their photophysics are studied in the solid state, in ethanol–water mixtures inducing aggregation, and after encapsulation in polystyrene nanoparticles. The dye substitution pattern controls aggregation-induced emission and intramolecular energy transfer efficiency, resulting in single-band or dual fluorescence and a strong increase in fluorescence quantum yield upon particle encapsulation.

Aroyl-S,N-ketene acetal bichromophores show enhanced emission upon aggregation and encapsulation. Partial energy transfer is controlled by substitution pattern and leads to aggregation induced dual emission (AIDE).