Beneficial synergy of adsorption-intercalation-conversion mechanisms in Nb2O5@nitrogen-doped carbon frameworks for promoted removal of metal ionsviahybrid capacitive deionization

Guizhi Wang, Tingting Yan, Junjie Shen, Jianping Zhang, Liyi Shi, Dengsong Zhang

Research output: Contribution to journalArticlepeer-review

Abstract

Capacitive deionization (CDI) is an emerging water purification technology, but the ion adsorption capacity of traditional carbon-based CDI electrodes is still unsatisfactory. Herein, a novel faradaic electrode by anchoring Nb2O5nanoparticles on nitrogen-doped carbon frameworks as anodes and activated carbon (AC) as cathodes in a hybrid capacitive deionization (HCDI) system was originally developed to capture Na+ionsviaadsorption-intercalation-conversion mechanisms. The synergistic effects of the nanostructure and carbon coating were beneficial to enhancing electrical conductivity and offering fast Na+ion diffusion pathways. Impressively, the HCDI system demonstrated an excellent ion adsorption capacity of 35.4 mg g−1in a 500 mg L−1NaCl solution at 1.2 V as well as stable regeneration ability.In situRaman andex situXPS measurements unraveled that the mechanism of ion removal from water was the reversible redox reaction of Nb2O5. The new overall understanding of the synergistic effects opens opportunities for the design of HCDI systems for efficient removal of metal ions from saline water.

Original languageEnglish
Pages (from-to)122-130
Number of pages9
JournalEnvironmental Science: Nano
Volume8
Issue number1
Early online date8 Dec 2020
DOIs
Publication statusPublished - Jan 2021

ASJC Scopus subject areas

  • Materials Science (miscellaneous)
  • Environmental Science(all)

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