Blowing Iron Chalcogenides into Two-Dimensional Flaky Hybrids with Superior Cyclability and Rate Capability for Potassium-Ion Batteries

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

15 Scopus Citations
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Author(s)

  • Hu Wu
  • Siyuan Xu
  • Jing Zhao
  • Yuankun Wang
  • Chang Huang
  • Amr Abdelkader
  • Wei Alex Wang
  • Kai Xi
  • Yuzheng Guo
  • Shujiang Ding
  • Guoxin Gao
  • Ramachandran Vasant Kumar

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)2506–2519
Journal / PublicationACS Nano
Volume15
Issue number2
Online published19 Jan 2021
Publication statusPublished - 23 Feb 2021

Abstract

Chalcogenide-based anodes are receiving increasing attention for rechargeable potassium-ion batteries (PIBs) due to their high theoretical capacities. However, they usually exhibit poor electrochemical performance due to poor structural stability, low conductivity, and severe electrolyte decomposition on the reactive surface. Herein, a method analogous to "blowing bubbles with gum" is used to confine FeS2 and FeSe2 in N-doped carbon for PIB anodes with ultrahigh cyclic stability and enhanced rate capability (over 5000 cycles at 2 A g-1). Several theoretical and experimental methods are employed to understand the electrodes' performance. The density functional theory calculations showed high affinity for potassium adsorption on the FeS2 and FeSe2. The in situ XRD and ex situ TEM analysis confirmed the formation of several intermediate phases of the general formula KxFeS2. These phases have high conductivity and large interlayer distance, which promote reversible potassium insertion and facilitate the charge transfer. Also, the calculated potassium diffusion coefficient during charge/discharge further proves the enhanced kinetics. Furthermore, The FeS2@NC anode in a full cell also exhibits high cyclic stability (88% capacity retention after 120 cycles with 99.9% Coulombic efficiency). Therefore, this work provides not only an approach to overcome several challenges in PIB anodes but also a comprehensive understanding of the mechanism and kinetics of the potassium interaction with chalcogenides.

Research Area(s)

  • "gel-blowing" strategy, fast ion transport, intermediate phases, iron chalcogenide, potassium-ion batteries

Citation Format(s)

Blowing Iron Chalcogenides into Two-Dimensional Flaky Hybrids with Superior Cyclability and Rate Capability for Potassium-Ion Batteries. / Wu, Hu; Lu, Shiyao; Xu, Siyuan; Zhao, Jing; Wang, Yuankun; Huang, Chang; Abdelkader, Amr; Wang, Wei Alex; Xi, Kai; Guo, Yuzheng; Ding, Shujiang; Gao, Guoxin; Kumar, Ramachandran Vasant.

In: ACS Nano, Vol. 15, No. 2, 23.02.2021, p. 2506–2519.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review