Preparation of Mechanically Exfoliated Graphite Sheet/Poly(3,4-ethylenedioxythiophene) Electrodes and the Study on Their Supercapacitive Properties

Graphite sheet (GS) is very promising for commercial use in SCs, due to its low cost and high conductivity. Nevertheless, the 2D flat surface of GS would limit the charge transport between GS and electroactive materials, because of the dissatisfactory interface being formed. Here, a facile mechanically exfoliated method is proposed to treat GS to obtain mechanically exfoliated GS (MEGS) as current collector, which shows a unique layered microstructures. And meanwhile, the electropolymerization parameter-dependent supercapacitive performance of the poly(3,4-ethylenedioxythiophene) (PEDOT) films as the electroactive material is investigated in detail. Electrochemical measurements verify that the electrochemical properties of PEDOT electrodes are substantially enhanced by using optimized electropolymerization parameters. More importantly, the electrochemical properties of PEDOT electrodes are further observably boosted through using MEGS current collector compared to GS, attributed to the 3D interface established between the PEDOT films and MEGS. The resulting MEGS/PEDOT electrodes yield areal capacitance of 96.2 mF center dot cm(-2) at 0.5 mA center dot cm(-2), superior rate performance, and remarkable cycling stability (90.6% of capacitance retention for 10000 cycles). Such characteristics of MEGS/PEDOT electrodes offer great promise in high performance supercapacitor applications. [GRAPHICS] .

Automated summary

Graphite sheet (GS) is commonly used as a current collector in supercapacitors, but its 2D flat surface limits charge transport. In this study, mechanically exfoliated GS (MEGS) is proposed as a current collector, which forms a unique layered microstructure. The electropolymerization parameters are optimized to enhance the electrochemical performance of poly(3,4-ethylenedioxythiophene) (PEDOT) films as the electroactive material. By using MEGS as the current collector, a 3D interface is established between the PEDOT films and MEGS, leading to significantly improved electrochemical properties of the PEDOT electrodes.