Study On Preparation And Capacitive Performance Of WS₂/PEDOTs Nanocomposites

In the face of the increasingly serious energy and environmental problems,the promotion of the use of clean energy has become one of the most effective ways to achieve sustainable development.The development of advanced electrochemical energy storage and conversion systems?such as supercapacitors,batteries and fuel cells?can enable the efficient storage and use of clean energy.Among them,supercapacitors have the advantages of wide operating temperature range,long service life,safety and reliability,low price and environmental friendliness,and have become one of the widely concerned energy storage devices in the energy storage field.The development of high performance and low cost electrode materials is a prerequisite for the large-scale application of electrochemical storage and conversion systems.Recently,WS₂ is a kind of two-dimensional layered graphene compound with strong orbital spin coupling,band splitting,nonlinearity and high sensitivity.Moreover,the single-layer WS₂ has the characteristics of wide direct bandgap width,high theoretical electron mobility and photoluminescent quantum yield,which makes it have potential application potential in the field of energy conversion and storage.In addition,the preparation methods of WS₂-based composites in many literatures are complicated,and most electrode materials prepared need to add non-conductive binder and less capacitive carbon black.In view of the above problems,this paper takes the composite material of WS₂ and CPs as the research object,and the electrode material is prepared by electrochemical polymerization and vacuum filtration.The composite materials were characterized by energy dispersive spectrometry,X-ray photoelectron spectrum and scanning electron microscope.Simultaneously,the conductivity and electrochemical properties of the composites were tested and evaluated by four-probe method and electrochemical method.The specific contents are as follows:?1?Single-layer or few-layer WS₂ nanosheets were prepared by chemical exfoliation.With the assistance of PEG,the PEDOT-PEG-WS₂ nanocomposite with3D interpenetrating porous network?3D IPN?was prepared by a simple,self-assembled electrochemical method.The results demonstrated the formation of 3D IPN PEDOT-PEG-WS₂ nanocomposites.Simultaneously,PEDOT-PEG-WS₂nanocomposites showed a high areal capacitance of 236.5m F cm^-2 at 5 m V s^-1,which is larger than that of PEDOT-PEG film(77.5m F cm^-2).The cycling stability was 91%of capacitive retention after 5000 charge-discharge cycles.The specific energy was 78?2?The PEDOT-Me OH/PEG/WS₂ composites were prepared by co-deposition method.The preparation of PEDOT-Me OH/PEG/WS₂ composite with porous poplar flower was proved by SEM.The area capacitance of the porous poplar-like PEDOT-Me OH/PEG/WS₂ composites was 461.5m F cm^-2 at 5 m V s^-1,which was superior to that of PEDOT-Me OH/PEG film.The cyclic stability was 85.8%after5000 charges and discharges.Additionally,the symmetrical device based on the porous poplar flower PEDOT-Me OH/PEG/WS₂ composite displayed a high areal capacitance of 253.3 m F cm^-2 at 15 m V s^-1.The capacitive retention rate was 83.6%of the initial capacitance and the coulomb efficiency reaches about 100%after 5000charge and discharge cycles.?3?The self-freestanding PEDOT:PSS/WS₂ film was prepared by vacuum filtration method.The formation of layered PEDOT:PSS/WS₂ film was proved by cross-SEM characterization.The composite film with a conductivity of 44 S cm^-1could withstand a weight of 300 g and be used as a wire in a circuit.Meanwhile,the PEDOT:PSS/WS₂ film exhibited high areal capacitance of 86 m F cm^-2 and volumetric capacitance of 411 F cm^-3 at 40 m V s^-1.Besides,the capacitance retention could reach 107%of initial specific capacitance after 5000 charge-discharge cycles.