Conjugated System of PEDOT:PSS-Induced Self-Doped PANI for Flexible Zinc-Ion Batteries with Enhanced Capacity and Cyclability

Ying Liu; Luoyuan Xie; Wang Zhang; Ziwen Dai; Wei Wei; Shaojuan Luo; Xian Chen; Wei Chen; Feng Rao; Lei Wang; Yang Huang

doi:10.1021/acsami.9b09802

Conjugated System of PEDOT:PSS-Induced Self-Doped PANI for Flexible Zinc-Ion Batteries with Enhanced Capacity and Cyclability

ACS Appl Mater Interfaces. 2019 Aug 28;11(34):30943-30952. doi: 10.1021/acsami.9b09802. Epub 2019 Aug 13.

Authors

Ying Liu^{1

2}, Luoyuan Xie¹, Wang Zhang^{1

2}, Ziwen Dai^{1

2}, Wei Wei³, Shaojuan Luo⁴, Xian Chen¹, Wei Chen⁵, Feng Rao¹, Lei Wang¹, Yang Huang¹

Affiliations

¹ College of Materials Science and Engineering , Shenzhen University , Shenzhen 518055 , China.
² Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering , Shenzhen University , Shenzhen 518060 , China.
³ Key Laboratory of Advanced Technologies of Materials (Ministry of Education), School of Materials Science and Engineering , Southwest Jiaotong University , Chengdu 610031 , China.
⁴ School of Chemical Engineering and Light Industry , Guangdong University of Technology , Guangzhou 510006 , China.
⁵ Institute of Medical Engineering, School of Basic Medical Sciences , Xi'an Jiaotong University , Xi'an 710061 , China.

PMID: 31364840
DOI: 10.1021/acsami.9b09802

Abstract

Owing to its electronic conductivity and electrochemical reactivity, polyaniline (PANI) can serve as the cathode for rechargeable zinc-ion batteries (ZIBs). However, it suffers from fast deactivation and thus performance deterioration because of spontaneous deprotonation during charge/discharge. Here, we report an effective strategy to improve the electrochemical reactivity and stability of the PANI-based cathode by constructing a π-electron conjugated system between PANI and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on carbon nanotubes (CNTs). The impressive performance of the post-treated CNTs-PANI-PEDOT:PSS (t-CNTs-PA-PE) cathode is largely attributed to the -SO₃^-H⁺ groups in PSS, which acts as an internal proton reservoir and provides enough H⁺ for PANI's protonation, thus promoting its electrochemical activity and reversibility. Besides, the strong interactions between PANI and PEDOT:PSS assist the stretching of π-π conjugation chains, bringing about enhanced electronic conductivity. Consequently, the t-CNTs-PA-PE cathode achieves a high capacity of 238 mA h g^-1, together with good rate capability and long-term stability (over 1500 cycles with 100% Coulombic efficiency). Through exerting the freestanding t-CNTs-PA-PE, a flexible ZIB was further constructed with both outstanding electrochemical properties and superior high safety. This work demonstrates the availability of conducting polymer cathodes for high-performance ZIBs, fulfilling the need of flexible electronics.

Keywords: PANI; PEDOT:PSS; Zn-ion batteries; conjugated system; enhanced performance.