3D flowerlike poly(3,4-ethylenedioxythiophene) for high electrochemical capacitive energy storage

Graphical abstract: The novel 3D flowerlike nanomaterial demonstrates high capacitive property on energy storage application. -- Highlights: • 3D conducting polymer are firstly reported as supercapacitor electrode materials. • 3D flowerlike morphology is favorable for electrons and ions transport. • 3D flowerlike PEDOT/MnO2 manifests much better cycle durability. • Sythesis approach of PEDOT/MnO2 may give rise to 3D new materials. • Quite small size MnO2 nanoparticles are well dispersed on conducting matrix. -- Abstract: The electrochemical performances of 3D flowerlike PEDOT are characterized by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. It shows high specific capacitance of 111 F g−1, which is greatly higher than that of 1D PEDOT nanofibers we reported before. In addition, on the basis of this PEDOT matrix, 3D flowerlike PEDOT/MnO2 composite is synthesized by a two-step approach as a high-property supercapacitor electrode material. Scanning and transmission electron microscopy show that 3D PEDOT matrix is kept well and decorated well by MnO2 nanoparticles (2–5 nm). And the capacitive performances are tested as well. The specific capacitance of this composite can highly reach around 183 F g−1, and retain more than 90% of the original value after 1000 consecutive charge/discharge cycles. These results indicate that the 3D flowerlike PEDOT/MnO2 composite possesses a synergy effect of complementary properties of both components, which results in higher specific capacitance and better stability