# Non-traditional fluorescence in quadruple hydrogen bonded supramolecular polymers

## TL;DR

Researchers created efficient luminescent polymers using hydrogen bonds, enabling strong fluorescence and useful material properties.

## Contribution

A new strategy using dynamic quadruple hydrogen bonding motifs to achieve high luminescence efficiency in supramolecular polymers.

## Key findings

- Supramolecular polyurethane achieved a photoluminescent quantum yield of up to 52%.
- Quadruple hydrogen bonds enable proton transfer and multifunctional material properties like self-healing and reprocessability.
- Ultrafast and solid-state NMR spectroscopy confirmed the role of hydrogen bonds in luminescence.

## Abstract

Non-traditional luminescent polymers exhibit significant advantages in bio-diagnostics and intelligent materials but suffer from low luminescence efficiency and limited functionality. Inspired by the excited-state proton transfer mechanism mediated by dense hydrogen bonds in jellyfish fluorescent proteins, we propose a strategy using dynamic quadruple hydrogen bonding ureidopyrimidinone motifs to create highly efficient luminescent polymers. By modulating the aggregated structure of the supramolecular units, proton transfer between paired motifs is activated, thereby achieving a high photoluminescent quantum yield up to 52% in supramolecular polyurethane. Ultrafast spectroscopy directly revealed this intermolecular proton transfer, while solid-state NMR spectroscopy confirmed the essential role of quadruple hydrogen bonds. The dynamically switchable hydrogen bonding structure endows the material with multifunctional integration, including strong fluorescence properties, high toughness, self-healing, reprocessability, and stimulus responsiveness. This research not only introduces a pioneering approach for advancing high-performance light-emitting materials but also enhances the prospects for their practical applications.

Non-traditional luminescent polymers are materials without extended π-conjugation. Here the authors develop highly luminescent supramolecular polymers using dynamic quadruple hydrogenbonded motifs with potential for sensing and fluorescent adhesives.