Preparation And Supercapacitor's Properties Of Transition Metalsulfide Composite Materials

In recent years,designing high-performance energy storage devices has become the main research goal of people due to the gradual depletion of non-renewable energy and the environmental pollution.Supercapacitors have attracted great research interest due to their high power density and long cycle life.Among many factors,the choice of electrode materials and the design of the structure are particularly important for the performance of supercapacitor.As advanced pseudocapacitive materials,transition metal sulfides have attracted extensive research by virtue of their high redox activity and high electrical conductivity.However,most of the sulfide synthesis methods are too complicated to be widely used.Therefore,the hierarchical structure of NiS₂/MoS₂?NMS?nanowires and Co3S4/Ni3S4/MoS2?CMS?nanosheet-nanorod arrays were synthesized by a one-step hydrothermal method.?1?NiS2/MoS2?NMS?nanowires were successfully synthesized by a one-step hydrothermal method,and the effects of hydrothermal times on their performance were analyzed.Due to the advantages of structure and composition,the NMS-12 electrode?12 refers to the hydrothermal reaction time of 12 h?exhibits a high areal capacitance of4.46 F cm^-2at 5 mA cm^-2.In addition,the device of NMS-12//AC displays a high energy density of 0.35 mWh cm-2 at a high power density of 3.63 mW cm-2,and prominent cycle stability with 92.4%retention after 3000 cycles.These results show that this electrode material has a good application prospect in supercapacitors.?2?The hierarchical of Co₃S₄/Ni₃S₄/MoS₂?CMS?nanosheet-nanorod arrays were synthesized by a hydrothermal method,and the growth process was proposed according to the morphological evolution of different hydrothermal time.The CMS-20 electrode?20 refers to the hydrothermal reaction time of 20 h?delivers an areal capacitance of3.94 F cm^-22 at 5 mA cm^-2,and prominent cycle stability with 91.8%capacitance retention after 5000 cycles.These results indicate that the CMS electrode developed in this paper has the potential to become a high-performance supercapacitor.