Homogeneous integration of SnS2 quantum dots with S, N-codoped layered graphene for robust lithium storage performance. (December 2022)

• Record Type: Journal Article
• Authors: Yin, Shujuan; Wang, Yishan; Zhang, Xueqian; Sheng, Yun; Lan, Bo; Wei, Chuncheng; Wen, Guangwu
• Is Part Of: Vacuum. Volume 206(2022)
• Publication Date: 2022-12
• Subjects: SnS2 quantum dots -- Graphene nanosheets -- In situ S -- N-codoping -- Lithium storage capacity; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2022.111482
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: Owing to the higher theoretical specific capacity and particular stratification construction, SnS2 materials are regarded as a potential high specific capacity anode electrode, but also have problems such as large initial irreversible capacity, low conductivity, and large volume changes during charging/discharging. Recently, SnS2 quantum dots (SnS2 QDs) with ultra-small particle sizes offer a possibility for the practical application of alleviating the volume expansion. Herein, the S, N-codoped three-dimensional porous graphene composites with ultra-small SnS2 particles (SnS2 QDs/SNG) by a simple one-step hydrothermal method using thiourea as sulfur source and reductant. The SnS2 QDs with a mean diameter of 2–3.5 nm can effectively short the ion channel and disperse the mechanical stress. In addition, the S, N-codoped graphene has a large specific surface area, which can alleviate the volume expansion. Profit from the 3D framework porous nanostructure, the resulting anode electrode shows a significant specific capacity and cycle stability of 1859.6 mAh g −1 after 100 cycles of 0.1A g −1, and still shows the capacity of 754.2 mAh g −1 after 1000 cycles of 0.5 A g −1 . This unique structural design and features provide a valuable reference for further research on the composite of SnS2 nanoparticles with graphene as anode material. Highlights: Graphene inhibits structural changes in SnS2 . SnS2 quantum dots shortens ion path. S, N co-doping provides active sites.