Graphene nanoscroll/nanosheet aerogels with confined SnS2 nanosheets: simultaneous wrapping and bridging for high-performance lithium-ion battery anodes. (10th July 2018)

• Record Type: Journal Article
• Authors: Zhang, Youfang; Zhao, Chenyang; Zeng, Zhihui; Ang, Jia Ming; Che, Boyang; Wang, Zhe; Lu, Xuehong
• Is Part Of: Electrochimica acta. Volume 278(2018)
• Page Start: 156
• Page End: 164
• Publication Date: 2018-07-10
• Subjects: Graphene nanoscrolls -- Transition metal dichalcogenide -- Aerogel -- Lithium ion batteries -- Porous structure; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.05.031
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: In this paper, we report graphene nanoscrolls bridged by crumpled graphene nanosheets as an effective conductive framework for confining SnS2 nanosheets for lithium-ion battery (LIB) applications. The nanoscroll/nanosheet hybrid aerogels (GNAs) with confined SnS2 nanosheets are facilely prepared via fast quenching, freeze-drying and thermal annealing. During quenching, wrapping SnS2 nanosheets in the nanoscrolls and bridging the one-dimensional nanoscrolls by the two-dimensional nanosheets occur simultaneously, and the ratio of nanoscrolls/nanosheets can be controlled by simply adjusting quenching conditions. The optimized SnS2 /GNA is highly porous with a large specific surface area of 127.1 m 2 g −1 and multi-scale pore structure, which can effectively prevent SnS2 aggregation to provide abundant lithiation/delithiation sites, and buffer volumetric change and pulverization of SnS2 nanosheets. Moreover, the three-dimensional conductive network formed in the hybrid aerogels can remarkably improve its electrical conductivity while providing sufficient channels for the transportation of lithium ions and charges. As a result, the optimized SnS2 /GNA nanocomposite exhibits enhanced electrochemical performance with a high initial reversible capacity (1514.8 mAh g −1 at 0.1 A g −1 ), excellent rate capacity (665.4 mAh g −1 at 5 A g −1 ) and good cyclic stability (1050 mA h g -1 at the 50 th cycle). This may provide an efficient generic approach for encapsulation of transition metal dichalcogenide materials in conductive nano/micro confined spaces for fabrication of high-performance LIB anodes. Graphical abstract: Highly porous nano-aerogels composed of controllable amounts of SnS2 -encapsulated hollow graphene nanoscrolls bridged by wrinkled SnS2 -attached graphene nanosheets are readily synthesized as excellent anode materials for lithium ion batteries. Image 1 Highlights: Highly porous graphene nanoaerogels with interconnected nanoscroll/nanosheet hybrid structure confine SnS2 successfully. The preparation method is simple and scalable. The unique 3D graphene configuration provides spacious inter-space to buffer SnS2 pulverization in cycling tests. The SnS2 /graphene composite exhibits high reversible capacity and coulombic efficiency, good cycling and rate capability.