Affiliation:
1. School of Energy and Chemical Engineering/Center for Dimension‐Controllable Organic Frameworks Ulsan National Institute of Science and Technology (UNIST) Ulsan 44919 South Korea
2. Key Laboratory of Automobile Materials (Jilin University), Ministry of Education, School of Materials Science and Engineering Jilin University Changchun 130012 China
Abstract
AbstractEfficient sodium ion storage in graphite is as yet unattainable, because of the thermodynamic instability of sodium ion intercalates–graphite compounds. In this work, sodium fluorozirconate (Na3ZrF7, SFZ) functionalized graphite (SFZ‐G) is designed and prepared by the in situ mechanochemical silicon (Si) replacement of sodium fluorosilicate (Na2SiF6, SFS) and functionalization of graphite at the same time. During the mechanochemical process, the atomic Si in SFS is directly replaced by atomic zirconium (Zr) from the zirconium oxide (ZrO2) balls and container in the presence of graphite, forming SFZ‐G. The resulting SFZ‐G, working as an anode material for sodium ion storage, shows a significantly enhanced capacity of 418.7 mAh g−1 at 0.1 C‐rate, compared to pristine graphite (35 mAh g−1) and simply ball‐milled graphite (BM‐G, 200 mAh g−1). In addition, the SFZ‐G exhibits stable sodium‐ion storage performance with 86% of its initial capacity retention after 1000 cycles at 2.0 C‐rate.