Indium Sulfide/Carbon-based Nanocomposite Materials For Electrochemical Performance

As the energy shortage and environmental pollution gradually become worldwide problem,and the novel energy storage become more importance in promoting technology sectors and speeding up economic development becomes more and more obvious.Nanotechnology has provided new ideas for the modification of materials and research of new materials,which is playing an impormant role in the field of new energy.In this paper,we used L-cysteine as sulfur source and InCl₃ as indium source to synthesize In₂S₃ through microwave-assisted hydrothermal method followed by annealing process.Typically,it is an effective way to enhance electrical conductivity,improve microstructure and prevent agglomeration inside the active materials,thus improve the electrochemical properties of materials through combining with graphene and carbon nanotube,which are named In₂S₃@rGO and In₂S₃@CNT,respectively.Then make them as the electrode materials for lithium-ion batteries,supercapacitor and oxygen evolution reaction.For In₂S₃@rGO nanocomposites,the increasing addition of graphene could influence the microstructure of the active materials,thus exhibit different electrochemical properties.As the electrode for lithium-ion batteries,the In₂S₃@rGO-1/2 shows best lithium storage properties.The In₂S₃@rGO-1/2 anode can deliver the first discharge capacity of 1288mAh/g and initial coulombic efficiency of 50%at the current density 0.5A/g.After 300 cycles,the capacity retains 572mAh/g and the coulombic efficiency is nearly 100%.As the electrode for supercapacitor,In₂S₃@rGO nanocomposites show the faraday capacitance characteristics and the In₂S₃@rGO-2/1 can deliver a best specific capacity of 312F/g at 1A/g.And the capacitance retention is about 90%after 10000 cycles.As the electrode for oxygen evolution reaction,the In₂S₃@rGO-1/1 delivers a lowest initial oxygen evolution potential of 302mV and Tafel slope of 99mV/dec in 1M KOH solution,and shows good stability at20mA/cm² for a long time under the test.For In₂S₃@CNT nanocomposites,with the increasing addition of carbon nanotube,the In₂S₃ nanoparticles are evenly dispersed in carbon nanotube network and formed a carbon coating structure.When the mass ratio of In₂S₃@CNT is 1/1,the product presents best electrochemical properties owing to the advantage of the structure.As the electrode for lithium-ion batteries,the product can deliver the first discharge capacity of 1395mAh/g and initial coulombic efficiency of 47%at the current density 0.5A/g.After 300 cycles,the capacity is 724mAh/g and the coulombic efficiency is nearly 100%.As the electrode for supercapacitor,the product can deliver a specific capacity of 212F/g at 1A/g.And the capacitance retention is 96%after 7000 cycles.As the electrode material for oxygen evolution reaction,the product delivers a lowest initial oxygen evolution potential of286mV and Tafel slope of 80mV/dec in 1M KOH solution,and shows good stability at 20mA/cm² for a long time under the test.