In-situ synthesis of graphene nanosheets encapsulated silicon nanospheres by thermal plasma for ultra-stable lithium storage. (31st October 2022)

• Record Type: Journal Article
• Authors: Yang, Zongxian; Liu, Chang; Liu, Xiang; Du, Yu; Jin, Huacheng; Ding, Fei; Li, Baoqiang; Ouyang, Yuge; Bai, Liuyang; Yuan, Fangli
• Is Part Of: Carbon. Volume 199(2022)
• Page Start: 424
• Page End: 430
• Publication Date: 2022-10-31
• Subjects: Lithium-ion batteries -- Silicon anode -- RF-Plasma -- Graphene nanosheets -- In-situ synthesis; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2022.08.039
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: Owing to its high capacity, silicon (Si) is a promising anode for meeting the escalating need for batteries with high energy density. Nonetheless, the substantial volumetric variation generated by lithiation/delithiation often results in the pulverization of Si, which substantially lowers its cycle stability. Graphene/graphene nanosheets (GNSs) with higher electrical conductivity and mechanical strength are anticipated to overcome these obstacles when employed as the coating matrix of silicon. Unfortunately, the majority of Si@graphene composites are not manufactured in situ, so that graphene is hardly to entirely encapsulate Si.The low-quality coating leads to the exposure of Si after cycles, resulting in a short cycle life. Herein, graphene nanosheets encapsulated silicon nanospheres (Si@GNSs) are synthesized in situ using a radio-frequency (RF) thermal plasma system, in which graphene and Si have strong interfacial chemical interactions. Further, free-standing Si@GNSs/reduced graphene oxide (Si@GNSs/rGO) paper was prepared using graphene oxide (GO) as a special 'binder'. When Si@GNSs/rGO paper is directly used as anode electrodes, it demonstrates a high reversible capacity (2270 mAh g −1 at 0.2 A g −1 ), outstanding rate performance (1569 mAh g −1 at 5.0 A g −1 ) and ultra-stable cycle performance (capacity retention of 98.55% for 2000 cycles at 3.0 A g −1 ). Graphical abstract: Image 1 Highlights: Si@GNSs composites were prepared in situ by the RF thermal plasma system. The flexible Si@GNSs/rGO paper is prepared with GO as a special 'binder'. Si@GNSs/rGO paper exhibits high capacity of 2250 mAh g −1 at 0.2 A g −1 . Si@GNSs/rGO paper show excellent rate performance of 1569 mAh g −1 at 5.0 A g −1 . After 2000 cycles, the capacity of Si@GNSs/rGO paper remains 98.55%.