Preparation Of Carbon-based Self-supported Film Electrode And Its Charge Storage Performance

With the rapid development of wearable electronic devices,flexible technology has become the focus of attention.Among them,the flexible supercapacitor has the characteristics of high power density,long cycle life and high safety.As an important part of flexible supercapacitor,electrode materials need to have good conductivity,excellent mechanical properties and stable electrochemical properties.Among many electrode materials,reduced graphene oxide(rGO)self-supported films electrode has attracted extensive attention due to its excellent electrochemical and mechanical properties.However,in the process of film formation,the uneven layer inside the film and the easy stacking of rGO nanosheets will lead to the deterioration of the overall performance of rGO films.In order to solve these two problems,this paper take rGO films as the object to carry out in-depth research,and the specific research content is as follows:(1)Preparation and properties of rGO/SWCNTs and rGO/TSG composite film electrodes.In the first,one-dimensional material SWCNTs was used to reduce the overall stacking degree of rGO films and the overall charge transfer efficiency of the selfsupported film electrodes can be increased.The electrical and electrical conductivity of the prepared rGO/SWCNTs self-supported films reached the highest of 30,000 S/m.When current density is 1 A/g,mass specific capacitance is 173 F/g.Then,twodimensional material TSG was used to improve the flatness of the inner layer of the films,so as to improve the mechanical properties of the films.The electrical and electrical conductivity of the rGO/TSG self-supported films was about 10000 S/m.The highest tensile strength is about 92 MPa.When the current density is 1 A/g,the mass specific capacitance is 162 F/g.(2)Preparation and properties of rGO/TSG/SWCNTs composite film electrodes.The synergistic effect of one-dimensional material SWCNTs and two-dimensional material TSG was used to improve the conductivity,mechanical properties and capacity of composite film electrodes.By microregulating the ratio between rGO,TSG and SWCNTs,when the mass ratio of the self-supporting film material was rGO:TSG:SWCNTs = 40:3:2,the conductivity reached 39,000 S/m and the tensile strength reached 95 MPa.Then,the tearing strength of the films were detected.Tear strength increased by about 2 times.(3)Preparation and Performance of Supercapacitor and Flexible Semi-solid Supercapacitor: In order to study the performance of self-supported film electrodes in energy storage devices,symmetric supercapacitors and flexible semi-solid supercapacitors were prepared based on rGO/TSG/SWCNTs film electrodes with optimal ratio.In the prepared flexible semi-solid supercapacitor,when the current density is 60 m A/cm3,the volume specific capacitance reaches 97.45 F/cm3.The initial capacitance retention rate reached 93.8% after 10000 GCD cycles.At different bending angles,the capacity of flexible devices is basically the same,indicating that they have good electrochemical stability and mechanical flexibility,flexible devices can satisfy some basic bending conditions and have good application prospects.