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Abstract The ability to assemble artificial systems that mimic aspects of natural light‐harvesting functions is fascinating and attractive for materials design. Given the complexity of such a system, a simple design pathway is desirable. Here, we argue that associative phase separation of oppositely charged conjugated polyelectrolytes (CPEs) can provide such a path in an environmentally benign medium: water. We find that complexation between an exciton–donor and acceptor CPE leads to formation of a complex fluid. We interrogate exciton transfer from the donor to the acceptor CPE within the complex fluid and find that transfer is highly efficient. We also find that excess molecular ions can tune the modulus of the inter‐CPE complex fluid. Even at high ion concentrations, CPEs remain complexed with significantly delocalized electronic wavefunctions. Our work lays the rational foundation for complex, tunable aqueous light‐harvesting systems via the intrinsic thermodynamics of associative phase separation.
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This content will become publicly available on July 6, 2026
Photophysical and Viscoelastic Properties of Ionically Complexed Conjugated Polyelectrolyte for Printed Soft Electronics
Abstract Conjugated polyelectrolytes (CPEs) exhibit a strong interplay between ionic and electronic properties, enabling tunable photophysical properties and charge transport dynamics. Polyelectrolyte complexation represents a versatile self‐assembly strategy to control the properties of CPEs by forming dense phases with varying optoelectronic and mechanical characteristics. This study focuses on ionically assembled complexes comprising oppositely charged self‐doped CPE (CPE‐K) and bottlebrush polyelectrolyte (BPE). It is demonstrated that subtle adjustments in the composition of CPE‐K:BPE blends enables tuning of photophysical and viscoelastic properties. It is observed that increasing the CPE‐K:BPE monomeric ratio from 1:1 to 1:3 in the initial solution for complexation induces a significant bathochromic shift in the maximum photoluminescence intensity of the dense phase, from 1.8 to 1.4 eV. Additionally, a higher BPE content enhances the softness and adhesion of the solid complex, while maintaining yield‐stress behavior and cyclability of the dense phase. The ability to electrochemically and statically dope the CPE‐K–BPE complex, effectively modulating its charge transport and optoelectronic properties is also demonstrated. This work underscores the potential of these complex‐fluid phases for developing soft, adhesive, and elastic mixed ionic‐electronic conductors with tunable properties for functional applications and 3D‐printing.
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- Award ID(s):
- 2323715
- PAR ID:
- 10639991
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The ability to assemble artificial systems that mimic aspects of natural light‐harvesting functions is fascinating and attractive for materials design. Given the complexity of such a system, a simple design pathway is desirable. Here, we argue that associative phase separation of oppositely charged conjugated polyelectrolytes (CPEs) can provide such a path in an environmentally benign medium: water. We find that complexation between an exciton–donor and acceptor CPE leads to formation of a complex fluid. We interrogate exciton transfer from the donor to the acceptor CPE within the complex fluid and find that transfer is highly efficient. We also find that excess molecular ions can tune the modulus of the inter‐CPE complex fluid. Even at high ion concentrations, CPEs remain complexed with significantly delocalized electronic wavefunctions. Our work lays the rational foundation for complex, tunable aqueous light‐harvesting systems via the intrinsic thermodynamics of associative phase separation.more » « less
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