Hierarchical Interconnected Expanded Graphitic Ribbons Embedded with Amorphous Carbon: An Advanced Carbon Nanostructure for Superior Lithium and Sodium Storage

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2018-09, Vol.14 (39), p.e1802221-n/a
• Main Authors: Yang, Wang, Yang, Wu, Zhang, Fan, Wang, Guoxiu, Shao, Guangjie
• Format: Article
• Language: English
• Subjects: Amorphous structure; Batteries; Carbon; Carbonization; Catalytic converters; Chelation; Defects; Electrochemical analysis; Electrode materials; expanded graphitic ribbons; Graphitization; hierarchical porous carbon; Ion adsorption; Lithium; lithium and sodium storage; Nanostructure; Nanotechnology; Porosity; Reaction kinetics; Ribbons; Sodium; Sodium-ion batteries; Structural hierarchy; Tapes (metallic)
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.201802221

Carbon materials have attracted considerable attention as anodes for lithium‐ion and sodium‐ion batteries due to their low cost and environmental friendliness. This work reports an advanced carbon nanostructure that takes advantage of the chelation effect of glucose and metal ions, which ensures the uniform dispersion of metal in the precursor. Thus, an effective catalytic conversion from sp3 to sp2 carbon occurs, enabling simultaneously formation of pores with catalyzed graphitic structures. Due to the low carbonization temperature and short carbonization time as well as the different catalytic degree of various metals, a series of expanded graphitic layers from 0.34 to 0.44 nm with defects and amorphous carbon structure are obtained. The structure not only offers accessible graphitic spacings for reversible lithium/sodium ion insertion, but also provides abundant active sites for lithium/sodium ion adsorption in the defects and amorphous structure. Moreover, the hierarchical interconnected porous structure combining graphitic ribbons is beneficial for fast electronic/ionic transport and favorable electrolyte permeation. More importantly, such advanced carbon materials prove their feasibility for balancing the pore structure and degree of graphitization. When serving as the electrode material for lithium‐ion and sodium‐ion batteries, excellent electrochemical performance along with fast kinetics and long cycle life is achieved. Hierarchical porous carbon with interconnected expanded graphitic ribbons and amorphous carbon is prepared by a facile method. This advanced carbon nanostructure not only provides a favorable electronic and ionic transport network, but also achieves reversible and stable lithium/sodium ion insertion and adsorption. Therefore, it exhibits superior electrochemical performances, especially stable cyclic performance and high rate capability.