We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
The Principle of Introducing Halogen Ions Into β-FeOOH: Controlling Electronic Structure and Electrochemical Performance.
- Authors
Zhang, Dongbin; Han, Xuzhao; Kong, Xianggui; Zhang, Fazhi; Lei, Xiaodong
- Abstract
Highlights: Halogen ion-incorporated β-FeOOH(X)s (X = F−, Cl−, Br−) were designed and fabricated successfully and showed good performance for negative electrodes of supercapacitors. The embedment of X− caused the change of Fe–O bond length and structural distortion of β-FeOOH, which resulted in the narrow band gap and good electric conductivity. The presence of unexpected high valence state (3 + δ) Fe element facilitated the adsorption for SO32− species endowing the β-FeOOH(X)s with good wettability in Na2SO3 electrolyte. Coordination tuning electronic structure of host materials is a quite effective strategy for activating and improving the intrinsic properties. Herein, halogen anion (X−)-incorporated β-FeOOH (β-FeOOH(X), X = F−, Cl−, and Br−) was investigated with a spontaneous adsorption process, which realized a great improvement of supercapacitor performances by adjusting the coordination geometry. Experiments coupled with theoretical calculations demonstrated that the change of Fe–O bond length and structural distortion of β-FeOOH, which is rooted in halogen ions embedment, led to the relatively narrow band gap. Because of the strong electronegativity of X−, the Fe element in β-FeOOH(X)s presented the unexpected high valence state (3 + δ), which is facilitating to adsorb SO32− species. Consequently, the designed β-FeOOH(X)s exhibited the good electric conductivity and enhanced the contact between electrode and electrolyte. When used as a negative electrode, the β-FeOOH(F) showed the excellent specific capacity of 391.9 F g−1 at 1 A g−1 current density, almost tenfold improvement compared with initial β-FeOOH, with the superior rate capacity and cyclic stability. This combinational design principle of electronic structure and electrochemical performances provides a promising way to develop advanced electrode materials for supercapacitor.
- Subjects
ELECTRONIC structure; BAND gaps; ELECTRIC conductivity; ELECTRONIC control; NEGATIVE electrode; SUPERCAPACITOR electrodes; BROMINE
- Publication
Nano-Micro Letters, 2020, Vol 12, Issue 1, pN.PAG
- ISSN
2311-6706
- Publication type
Article
- DOI
10.1007/s40820-020-00440-2