Cu3(PO4)2/C composite as a high-capacity cathode material for rechargeable Na-ion batteries. (September 2016)

• Record Type: Journal Article
• Authors: Zhao, Wengao; Zhong, Guiming; McDonald, Matthew J.; Gong, Zhengliang; Liu, Rui; Bai, Jingyu; Yang, Chun; Li, Shiguang; Zhao, Weimin; Wang, Hongchun; Fu, Riqiang; Jiang, Zheng; Yang, Yong
• Is Part Of: Nano energy. Volume 27(2016:Sep.)
• Page Start: 420
• Page End: 429
• Publication Date: 2016-09
• Subjects: Conversion-type materials -- High capacity -- Cu3(PO4)2/C -- Rechargeability -- Solid-state NMR -- XAFS techniques; 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.2016.07.011
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Conversion-type materials are an appealing alternative to conventional intercalation compounds as cathode materials for sodium ion batteries, due to their high capacities. In this paper, we report for the first time that carbon-coated copper phosphate (Cu3 (PO4 )2 /C) can be used as a novel high-capacity cathode for rechargeable Na batteries. Cu3 (PO4 )2 /C shows a reversible capacity up to 290 mA h g −1 at a current of 20 mA g −1 and 190 mA h g −1 at 400 mA g −1, with capacity retention of 210 and 160 mA h g −1 respectively after 30 cycles. The detailed sodium storage mechanisms were studied by employing ex -situ XRD, HR-TEM, solid-state NMR and XAFS techniques. The results clearly indicate that Cu3 (PO4 )2 can transform into Na3 PO4 and Cu particles after discharge. Furthermore, Cu can react with Na3 PO4 to form copper phosphate and Nax Cuy PO4 in the charge process, determining the rechargeability of Cu3 (PO4 )2 . Graphical abstract: The schematic preparation approach of Cu3 (PO4 )2 /C and its electrochemical (de)sodiation reaction at 1st rechargeable cycle. Highlights: For the first time, Cu3 (PO4 )2 /C is reported as a novel cathode vs Na + /Na. High rechargeable specific capacity of the material as high as 290 mA h g −1. Acceptable capacity retention of 210 mA h g −1 (20 mA g −1 ) after 30 cycles. The detailed conversion reaction mechanism of Cu3 (PO4 )2 /C is disclosed.