SnS2 Nanosheets with RGO Modification as High-Performance Anode Materials for Na-Ion and K-Ion Batteries

Leqiang Wu,Yanli Zhou,Wei Du,Xiaoyu Zhang,Fuyi Jiang,Hengjia Shao,Xiangmin Feng,Caifu Dong,Zhijun Xu,Xueqin Sun,Linxuan Han,Chen Yang

doi:10.3390/nano11081932

Abstract

To date, the fabrication of advanced anode materials that can accommodate both Na+ and K+ storage is still very challenging. Herein, we developed a facile solvothermal and subsequent annealing process to synthesize SnS2/RGO composite, in which SnS2 nanosheets are bonded on RGO, and investigated their potential as anodes for Na+ and K+ storage. When used as an anode in SIBs, the as-prepared SnS2/RGO displays preeminent performance (581 mAh g−1 at 0.5 A g−1 after 80 cycles), which is a significant improvement compared with pure SnS2. More encouragingly, SnS2/RGO also exhibits good cycling stability (130 mAh g−1 at 0.3 A g−1 after 300 cycles) and excellent rate capability (520.8 mAh g−1 at 0.05 A g−1 and 281.4 mAh g−1 at 0.5 A g−1) when used as anode for PIBs. The well-engineered structure not only guarantees the fast electrode reaction kinetics, but also ensures superior pseudocapacitance contribution during repeated cycles, which has been proved by kinetic analysis.

Highlights

With the intensification of environmental pollution, green renewable energy has currently become an active area of research [1,2]
The fast electrode reaction kinetics and superior pseudocapacitance contribution may be the reason for the excellent performance, which has been proved by kinetic analysis
The precursor annealed at 350 ◦ C with a heating rate of 2 ◦ C min−1 in Ar gas for 1 h to gain the final products of SnS2 /RGO

Summary

Introduction

With the intensification of environmental pollution, green renewable energy has currently become an active area of research [1,2]. The low capacity of commercial graphite anodes for Na-ion and K-ion storage has greatly limited the large-scale development of SIBs and PIBs [6,7,8]. It is imperative to develop high-performance anode materials for both SIBs and PIBs. the hexagonal tin (IV) sulfide (SnS2 ) possesses unique two-dimensional (2D) layered structure with large interlayer spacing and high specific capacity based on both conversion and alloying processes [9,10,11], which makes it more appropriate for Na-ion and K-ion storage. Similar to other TMSs, SnS2 has the low intrinsic conductivity and the dramatic volume and structural changes, which will lead to the poor sluggish kinetics and rapid capacity reduction in the process of Na+ and K+

Methods

Results

Conclusion