Enabling Superior Sodium Capture for Efficient Water Desalination by a Tubular Polyaniline Decorated with Prussian Blue Nanocrystals

Wenhui Shi, Xiaoyue Liu, Tianqi Deng, Shaozhuan Huang, Meng Ding, Xiaohe Miao, Chongzhi Zhu, Yihan Zhu, Wenxian Liu, Fangfang Wu, Congjie Gao, Shuo Wang Yang, Hui Ying Yang, Jiangnan Shen*, Xiehong Cao*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

177 Citations (Scopus)

Abstract

The application of electrochemical energy storage materials to capacitive deionization (CDI), a low-cost and energy-efficient technology for brackish water desalination, has recently been proven effective in solving problems of traditional CDI electrodes, i.e., low desalination capacity and incompatibility in high salinity water. However, Faradaic electrode materials suffer from slow salt removal rate and short lifetime, which restrict their practical usage. Herein, a simple strategy is demonstrated for a novel tubular-structured electrode, i.e., polyaniline (PANI)-tube-decorated with Prussian blue (PB) nanocrystals (PB/PANI composite). This composite successfully combines characteristics of two traditional Faradaic materials, and achieves high performance for CDI. Benefiting from unique structure and rationally designed composition, the obtained PB/PANI exhibits superior performance with a large desalination capacity (133.3 mg g−1 at 100 mA g−1), and ultrahigh salt-removal rate (0.49 mg g−1 s−1 at 2 A g−1). The synergistic effect, interfacial enhancement, and desalination mechanism of PB/PANI are also revealed through in situ characterization and theoretical calculations. Particularly, a concept for recovery of the energy applied to CDI process is demonstrated. This work provides a facile strategy for design of PB-based composites, which motivates the development of advanced materials toward high-performance CDI applications.

Original languageEnglish
Article number1907404
JournalAdvanced Materials
Volume32
Issue number33
DOIs
Publication statusPublished - 1 Aug 2020
Externally publishedYes

Keywords

  • Faradaic electrodes
  • Prussian blue
  • capacitive deionization
  • polyaniline
  • water desalination

Cite this