Enabling superior hybrid capacitive deionization performance in NASICON-structured Na3MnTi(PO4)3/C by incorporating a two-species redox reaction. Issue 11 (24th February 2021)

• Record Type: Journal Article
• Authors: Wang, Shiyong; Wang, Gang; He, Chi; Gao, Ningbo; Lu, Bing; Zhao, Lin; Weng, Jiaze; Zeng, Shanshan; Li, Changping
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 11(2021)
• Page Start: 6898
• Page End: 6904
• Publication Date: 2021-02-24
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0ta11042f
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Na3 MnTi(PO4 )3 /C with two-species redox reactions was evaluated as an HCDI electrode for the first time that showed a high CDI performance. Abstract : Capacitive deionization (CDI) is a robust water treatment technique due to its energy-efficient, low cost, and environmentally safe features. Recently, the utilization of faradaic electrode materials to construct hybrid capacitive deionization (HCDI) is considered to be one of the effective ways to address the drawbacks of the inferior desalination capacity of conventional CDI. Here, for the first time, a Na3 MnTi(PO4 )3 /C (NTMP/C) composite was prepared via a sol–gel-calcination method and used as a faradaic electrode in HCDI. The NTMP nanoparticles were encapsulated in a carbon matrix, which could reduce the ion diffusion distance as well as ensure rapid ion transmission. In addition, taking the advantage of the high ratio of pseudo-capacitive performance and the two-species redox reaction of Ti 4+ /Ti 3+ and Mn 3+ /Mn 2+ couples, the obtained NTMP/C composite displayed a large ion removal capacity (72.2 mg g −1 ) (IRC), ultrafast ion removal rate (IRR) (21.6 mg g −1 min −1 ) and excellent cycle stability. Moreover, the mechanism of the Na + removal of NTMP/C in the desalination process was investigated via electrochemical and ex situ structural characterization. This study indicates that NTMP/C can be an alternative faradaic electrode material towards CDI applications.