Self-assembly flower-like porous carbon nanosheet powders for higher lithium-ion storage capacity. (1st December 2015)

• Record Type: Journal Article
• Authors: Ma, Zhen; Cui, Yan; Zuo, Xiaoxi; Sun, Yanhui; Xiao, Xin; Nan, Junmin
• Is Part Of: Electrochimica acta. Volume 184(2015)
• Page Start: 308
• Page End: 315
• Publication Date: 2015-12-01
• Subjects: lithium-ion batteries -- self-assembly -- carbon nanosheet powders -- spray drying -- path-memory effect; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2015.09.098
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: A novel nanomaterial of flower-like porous carbon nanosheet powders (CNPs) is prepared. The CNPs exhibit almost double theoretical capacity of prototype graphite powders and stable cycling performance. A 'path memory effect' is put forward to explain its good cycle performance in detail. Abstract: Based on the concepts of self-assembly and re-construction, flower-like porous carbon nanosheet powders (CNPs), which exhibit almost double theoretical capacity of prototype graphite powders, are prepared by spray drying a suspension of graphite oxide and cetyltrimethylammonium bromide (CTAB) and subsequent thermally-reducing treatment. The functional groups, edges, and defective sites of nanoscale graphite oxide intermediate and their interaction with CTAB additive are utilized to construct the CNP micro-/nanostructure with abundant wrinkles. This unique micro-/nanostructure not only facilitates coating CNPs on the anode substrate of lithium-ion batteries (LIBs) but also improves their electrochemical performances. Specifically, these CNPs display an initial specific capacity of approximately 807 mAh g −1 and a stable capacity of approximately 650 mAh g −1 after the 6 th cycle at a charge-discharge current of 100 mA g −1 . And a capacity of approximately 600 mAh g −1 is still kept after 100 cycles, showing the as-prepared CNPs have promising application in the LIBs. In addition, based on the insertion/extraction 'path-memory effect', a storage mechanism of lithium ions is proposed to explain the importance of wrinkles in the CNPs to the capacity and cycling stability.