Polyester Textile Supercapacitor Based On Polyaniline/Graphene Composite

With the gradual depletion of fossil energy and deterioration of the earth’s environment,it is urgent for people to develop environment-friendly and sustainable energy and corresponding energy storage devices.Supercapacitors play an irreplaceable role in energy storage device because of their advantages such as high power density and long work life.With the rapid development of portable electronic devices,flexible and wearable supercapacitors have great application prospects in the field of portable energy storage devices.How to make flexible supercapacitors with high wearable performance and energy storage performance at the same time.This is an urgent problem to be solved in current research.The key to develop wearable supercapacitors is preparing flexible electrodes.In this paper,cheap daily polyester textile is selected as the flexible substrate.By loading graphene,polyester textile can be turned into conductive textile.Subsequently,polyaniline/graphene polyester textile electrode is prepared by electrochemical deposition of polyaniline(PANI)on graphene coated polyester textile.The effects of the PANI ratio on the textile electrode’s structure and properties are systematically studied.Thus,a method of fabricating textile electrode with high flexibility and high capacitance is developed.The specific research contents are as follows:(1)Polyester textile supercapacitor based on polyaniline/LPE graphene composite:Graphene ink was prepared by liquid phase exfoliation(LPE)of graphite powder in NMP.And its concentration was improved to 6.51 mg/m L by selecting the appropriate particle size of graphite powder,increasing the initial concentration of graphite dispersion and prolonging the ultrasonic time.Subsequently,graphene polyester textile(GPT)was prepared by repeatedly"soaking-drying"the polyester textile in graphene ink.Then,PANI/GPT electrode was prepared by electrochemical deposition of PANI on GPT.The ratio of PANI in the textile electrode had been systematically modified and the obtained textile electrode possesses good energy storage performance.The mass specific capacitance of PANI/GPT reached 646.25 F/g at 1 A/g and 427.25 F/g can be maintained while the current density increased to 10A/g.The areal specific capacitance can also reach 243.88 m F/cm~2 at 1 m A/cm~2.Two PANI/GPT were assembled into a symmetric supercapacitor and the specific capacitance of the electrode reached 590.00 F/g at the current density of 1 A/g.The supercapacitor had good cyclic stability with 75.55%capacitance retention after 5,000cycles.Moreover,the device also exhibited excellent flexibility that can be bent with angle from 0°to 180°and the specific capacitance can still maintain 95.10%after 5,000repeated bending cycles.(2)Polyester textile supercapacitor based on polyaniline/RGO composite:The graphene oxide(GO)dispersion was prepared by a modified Hummers method.Through repeatedly"soaking-drying"the polyester textile in GO dispersion,GO coated polyester textile was prepared.Then it was reduced by a reductant and converted to RGO coated polyester textile(RPT).The effect of different reductant and reduction time on the structure and conductivity of RPT was emphatically studied.The results showed that the RPT obtained by reducing with HI solution for 12 hour possesses high conductivity,and the surface RGO combined well with the textile.Then,PANI/RPT electrode was prepared by electrochemical deposition of PANI on RPT.The ratio of PANI in the textile electrode had been systematically modified and the obtained textile electrode possessed excellent energy storage performance.The specific capacitance of PANI/RPT reached 888.50 F/g at 1 A/g and 500.25 F/g can be maintained while the current density increased to 10 A/g.The areal specific capacitance can also reach310.38 m F/cm~2 at 1 m A/cm~2.Two PANI/RPT were assembled into a symmetric supercapacitor.The device not only had good energy storage performance,but also possessed excellent cyclic stability with 83.57%capacitance retention after 10,000cycles.Moreover,the device also exhibited excellent flexibility that can be bent with angle from 0°to 180°and the specific capacitance can still maintain 92.18%after10,000 repeated bending cycles.In summary,different methods were used to load graphene on the surface of polyester textile,and further electrochemical deposition of polyaniline.Textile composite electrodes with good flexibility and energy storage performance were prepared to solve the problem that supercapacitors need good flexibility and energy storage performance at the same time.This method is easy to be popularized and has great application potential in the field of wearable energy storage devices.