Recent material development and applications of conjugated polyelectrolytes by leveraging electronic and ionic transport properties

Conjugated polyelectrolytes (CPEs) are a distinct class of organic materials featuring a π-conjugated backbone and ionic functional groups, enabling simultaneous electronic and ionic transport. This dual conductivity, governed by molecular design, makes CPEs highly versatile for a wide range of applications. The interplay between backbone conjugation and side-chain polarity allows fine-tuning of charge transport, significantly influencing their performance in electronic and energy storage devices. This review highlights recent advances in CPE material design, focusing on backbone evolution and side-chain engineering. We further explore key applications of CPEs, including organic photovoltaics, organic electrochemical transistors, and lithium-ion batteries, emphasizing the structural requirements for each field. Their current challenges and future opportunities are discussed, underscoring the critical role played by CPEs in next-generation optoelectronic and energy technologies.