Excitonically Coupled Simple Coacervates via Liquid/Liquid Phase Separation

J Phys Chem Lett. 2022 Nov 10;13(44):10275-10281. doi: 10.1021/acs.jpclett.2c02466. Epub 2022 Oct 28.

Abstract

Viscoelastic liquid coacervate phases that are highly enriched in nonconjugated polyelectrolytes are currently the subject of highly active research from biological and soft-materials perspectives. However, formation of a liquid, electronically active coacervate has proved highly elusive, since extended π-electron interactions strongly favor the solid state. Herein we show that a conjugated polyelectrolyte can be rationally designed to undergo aqueous liquid/liquid phase separation to form a liquid coacervate phase. This result is significant both because it adds to the fundamental understanding of liquid/liquid phase separation but also because it opens intriguing applications in light harvesting and beyond. We find that the semiconducting coacervate is intrinsically excitonically coupled, allowing for long-range exciton diffusion in a strongly correlated, fluctuating environment. The emergent excitonic states are comprised of both excimers and H-aggregates.

MeSH terms

  • Diffusion
  • Hydrogen-Ion Concentration
  • Polyelectrolytes
  • Water*

Substances

  • Polyelectrolytes
  • Water