Preparation Of Antimony Sulfide By Hydrothermal And Electrochemical Deposition Methods And Its Electrochemical Properties

With the rapid development of industrialization and the continuous growth of population,people’s demand for energy is also growing.As energy storage devices,supercapacitors have attracted great attention and research in recent years due to their due to high stability capacitance,fast charge and discharge,high power density and good cycle stability.The performance of supercapacitors depends on the structure and properties of the electrode materials.Sb₂S₃ semiconductor materials are a development direction of supercapacitor electrode materials due to their simple preparation method,narrow band gap and high stability.When it is used as a film material,it is examined whether it can be applied to the field of microcapacitors.In this work,two structures of Sb₂S₃ materials were prepared by hydrothermal method and electrochemical deposition method,one is Sb₂S₃ nanomaterials and the other is Sb₂S₃ thin film materials,respectively.Besides,their electrochemical properties were studied.During the hydrothermal research,the effects of reaction temperature,time and surfactant PVP addition on the morphology and structure of Sb₂S₃ nanomaterials were investigated.The results indicate that as the reaction time increases,the product Sb₂S₃gradually changes from an irregular rod shape to an elongated uniform nanorod and the dispersibility becomes better as well.When the reaction time is 24 h,the diameter of the nanorods is about 150-350 nm and the length is about 3-9μm.And the nanorods under this condition mainly grow along the（211）.And whether the reaction temperature is lower or higher,the nanorods become short and agglomerated.As the amount of PVP added increases,its morphology changes from nanorods to bundles and then becomes a double cauliflower.The Sb₂S₃ nanomaterials obtained under different amounts of PVP were coated on foamed nickel for electrochemical performance testing.The results show that the area specific capacitance and mass specific capacitance of the electrode with a 0.2 g PVP at a current density of 1 mA/cm² are 36.93 mF/cm² and 56.82 F/g,respectively.After 1000 cycles of charge and discharge,the specific capacity value remains as above the initial 85%.Moreover,during the electrochemical deposition study,the effects of deposition potential,time,reactant molar ratio and annealing temperature on the microstructure and structural composition of Sb₂S₃ thin films were investigated.The results show that when the deposition potential is between-0.65 V and-0.75 V,the overall morphology of the film is good,showing a porous structure,and the grain size is relatively uniform.Also the film composition is about Sb:S=2:3.The thickness of the film increases with the deposition time and the thickness is about 3-5μm with the time is during 5-10min.When the molar ratio of SbCl₃ to Na₂S₂O₃ is 2:3,the purity of the film is the highest.It is found that the crystallization of the thin film increases with the annealing temperature increased,and the grains also grow.By the way,the electrochemical properties of Sb₂S₃thin films prepared at different deposition potentials were investigated in 0.5 M Na₂SO₄solution.It is found that the capacitors prepared at a deposition voltage of-0.70 V have the best capacitor performance.In addition to,the mass specific capacitance and volume specific capacitance are 117.63 F/g and 20.39 F/cm³,respectively which at a current density of 1 mA/cm².After 1000 cycles of charge and discharge,the specific capacity value remains as above the initial 86%.