Graphene supported In2S3 nanostructure as electrode material for lithium sulfur batteries and supercapacitors

Abstract

A facile one-pot fabrication of reduced graphene oxide (rGO) supported In2S3-rGO is presented here with improved electrochemical performance in lithium-sulfur (Li–S) batteries and supercapacitors (SCs). Increasing the concentration of rGO in the nanostructures successfully mitigated the conversation kinetics, polysulfide shuttle effect and improved the overall cyclability in Li–S batteries. A battery made from In2S3-rGO30 electrode loses only 8 % of its discharge capacity after 250 continuous charge-discharge cycles, compared to a 36 % loss from a bare In2S3 electrode. It presented a high discharge capacity of 947.3 mA h g−1 at 1C, superb rate performance of 821.65 mA h g−1 at 5C, excellent capacity retention and Columbic efficiency of ⁓100 % over 250 cycles are achieved. The In2S3-rGO30 electrode provides a specific capacitance of 645.2 F g−1 at a current density of 2 A g−1 for SC application. The electrode retains 96 % of its capacity after 1000 continuous discharge cycles at a higher current density of 5 A g−1, performing well and staying ahead of other nanocomposites. This study successfully demonstrates the integration of In2S3 with a two-dimensional conductive substrate as a multifunctional and cost-effective host for designing high-performance cathode for Li–S batteries and battery-type electrode material for SC application.