An in-depth study of heteroatom boosted anode for potassium-ion batteries. (December 2020)

• Record Type: Journal Article
• Authors: Shen, Chao; Song, Ganqiang; Zhu, Xiuli; Wang, Dong; Huang, Lu; Sun, Zhenhe; Wu, Yingpeng
• Is Part Of: Nano energy. Volume 78(2020)
• Publication Date: 2020-12
• Subjects: Metal sulfide -- C–S bonds -- Nitrogen/Sulfur heteroatom -- Potassium-ion batteries -- Cyclic voltammetry measurement; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2020.105294
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Metal sulfide materials have been investigated extensively as anodes for alkali metal ion batteries. In this work, the N-doped graphene/bismuth sulfide (NGBS) composites are prepared for potassium-ion batteries (PIBs) anode and deliver an excellent electrochemical performance in K-ion storage. The N-doped graphene armor can accommodate the large volume variation and the weak electrical conductivity of the bismuth sulfide electrode, but also provides more active sites for K-ion storage which obviously enhances the specific capacity. Moreover, the active sites of the graphene play a crucial role in restricting the "shuttle effect" of polysulfide by forming C–S bonds reversibly during electrochemical redox process and achieve the stable electrochemical cycles as a hybrid anode for PIBs. The K-ion insertion/deinsertion and the reversible C–S bonds formation of the NGBS electrode during the electrochemical cyclic process are revealed by the in-situ X-ray diffraction, in-situ Raman spectroscopy, cyclic voltammetry and X-ray photoelectron spectroscopy in detailed. Graphical abstract: Metal sulfide possesses promising applications as an anode for potassium-ion batteries (PIBs) due to its high theoretical gravimetric capacity (625 mAh g −1 ). In this work, N-doping reduced graphene oxide-bismuth sulfide (NGBS) composites are adopted as an anode for PIBs. The results demonstrate that the N-doping graphene armor not only supplies more K-inserted sites with a higher specific capacity, but also restricts the shuttle effect of sulfur by trapping sulfur during the charge/discharge process with C–S bonds. Therefore, the NGBS electrode achieves an excellent cycle performance for PIBs (even at the current density of 10 A g −1, keeping specific capacity at 327 mAh g −1 ). Image 1 Highlights: N-doped rGO/Bi2 S3 (NGBS) composite was prepared for potassium-ion batteries anode with high performances. For the first time, reversible C–S bonds in NGBS anode were observed and studied during the electrochemical cycles. N-doped graphene improved the reversible capacity and cycling stability of the anode. The working mechanism of NGBS anode is revealed by the in-situ XRD, in-situ Raman spectroscopy, CV and XPS.