Conjugated Polyelectrolyte Thin Films for Pseudocapacitive Applications

Conjugated Polyelectrolyte Thin Films for Pseudocapacitive Applications

Yip, Benjamin Rui Peng (National University of Singapore)
Javier Vázquez, Ricardo (National University of Singapore)
Jiang, Yan (National University of Singapore)
McCuskey, Samantha R. (National University of Singapore; Nanyang Technological University)
Quek, Glenn (National University of Singapore)
Ohayon, David (National University of Singapore)
Wang, Xuehang (TU Delft RST/Storage of Electrochemical Energy)
Bazan, Guillermo C. (National University of Singapore; Nanyang Technological University; University of California)

2023

A subclass of organic semiconductors known as conjugated polyelectrolytes (CPEs) is characterized by a conjugated backbone with ionic pendant groups. The water solubility of CPEs typically hinders applications of thin films in aqueous media. Herein, it is reported that films of an anionic CPE, namely CPE-K, drop cast from water produces single-component solid-state pseudocapacitive electrodes that are insoluble in aqueous electrolyte. That X-ray diffraction experiments reveal a more structurally ordered film, relative to the as-obtained powder from chemical synthesis, and dynamic light scattering measurements show an increase in aggregate particle size with increasing [KCl] indicate that CPE-K films are insoluble because of tight interchain contacts and electrostatic screening by the electrolyte. CPE-K film electrodes can maintain 85% of their original capacitance (84 F g⁻¹) at 500 A g⁻¹ and exhibit excellent cycling stability, where a capacitance retention of 93% after 100 000 cycles at a current density of 35 A g⁻¹. These findings demonstrate that it is possible to use initially water soluble ionic-organic materials in aqueous electrolytes, by increasing the electrolyte concentration. This strategy can be applied to the application of conjugated polyelectrolytes in batteries, organic electrochemical transistors, and electrochemical sensors, where fast electron and ion transport are required.

conjugated polyelectrolytes
cycling stability
high-rate capability
pseudocapacitors

http://resolver.tudelft.nl/uuid:b9b45940-05c0-4b81-8349-40b54d946bbd

https://doi.org/10.1002/adma.202308631

2024-04-28

0935-9648

Advanced Materials, 36 (1)

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2023 Benjamin Rui Peng Yip, Ricardo Javier Vázquez, Yan Jiang, Samantha R. McCuskey, Glenn Quek, David Ohayon, Xuehang Wang, Guillermo C. Bazan