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The rapid development of current wearable electronics motivates the promotion of energy storage devices. Supercapacitor with flexible, lightweight, highly efficient, and long cycling life is one of the potential and glittering candidates. Here, the composite film of carboxylated graphene (CG) and commercially available poly (3, 4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT:PSS) are prepared as electrodes for flexible electrochemical capacitors by ultrasonication and vacuum filtration. The CG/PEDOT:PSS films were roundly characterized by SEM, XPS, FTIR, XRD and Raman spectrometer. The as-prepared free-standing films exhibited high specific capacitance (192.7 F g-1 at 0.5 A g-1), excellent rate capability (up to 80.4% from 0.5 to 20 A g-1), and good electrochemical stability (95.5% of specific capacitance retention after 50000 cycles). Surprisingly, the post treated free-standing films by Dimethyl Formamide (DMF) shows better capacitive properties than those of the pristine electrode, such as higher specific capacitance (204.3 F g-1 at 0.5 A g-1), and ultralong-cycling stability (104.6% retention at a high current density of 20 A g-1 after 50000 cycles). It is expected that the free-standing CG/PEDOT:PSS films can be used as flexible electrodes for various wearable energy storage devices. [ABSTRACT FROM AUTHOR]

Summary: Poly(2,7‐bis(carbazol‐9‐yl)‐9,9‐dimethylfluorene) (PBCMF) polymer with porous structure was fabricated, and its electropolymerization was studied comparatively in dichloromethane (CH2Cl2) systems in the presence of different contents of boron trifluoride diethyl etherate (BFEE). When adding BFEE in CH2Cl2 solution, the oxidation potential of BCMF could be decreased obviously. When the content of BFEE increased to 40%, BCMF was oxidized at 0.47 V, while it was oxidized at 1.07 V in pure CH2Cl2 solution. A series of experiments showed that the polymer PBCMF films could be easily obtained in CH2Cl2‐BFEE systems, and films obtained from the 40 vol% BFEE system showed best electrochemical behavior and best fluorescence property. Fourier transform infrared spectra and UV‐Vis proved the longer conjugated chains of polymers. And scanning electron microscopy images of polymer films showed that all these polymer films made from BFEE systems had a good porous structure. [ABSTRACT FROM AUTHOR]

Summary: As one kind of conducting polymer composite, poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) has been widely used as an electrode for energy storage and conversion devices because of its optical transmittance, flexibility, and high electrical conductivity etc. Here, we prepared binding‐free PEDOT:PSS fibers (PFs) electrodes with high capacitive performance for supercapacitors via a facile method followed by various solvent treatments. Dimethyl sulfoxide (DMSO)‐treated electrodes displayed a better specific capacitance (Cs) of 202 F/g at 0.5 A/g with higher elongation at break, flexibility, and conductivity of 140.7 S/cm, compared to those of pristine PEDOT:PSS materials. More importantly, the DMSO‐treated fibers possessed improved stability, which retained 105% of the initial Cs after 22 000 long cycles at 10 A/g. It is believed that the fabricated PFs will be promising organic electrodes for portable supercapacitors and other flexible electronic devices in the near future. [ABSTRACT FROM AUTHOR]

Summary: Polyaniline (PANI), a low‐cost conducting polymer with an excellent specific capacitance and a high conductivity, is a promising organic material served for supercapacitor. However, it tends to curl and swell after constant charge and discharge, resulting in poor cycle stability. In this work, we employed the interfacial polymerization route to construct an aniline‐grafting graphene oxide/PANI (GO‐ANI/PANI) composite. The as‐prepared GO‐ANI/PANI composite shows a high specific capacitance (160.5 F g‐1) at 0.5 A g‐1 under the wide potential range from 0.0 to 1.0 V. Importantly, at a high current density (10 A g‐1), the capacitance retains 86% after 3000 cycles due to the enhanced interaction between GO and PANI and good conductive network. It has been demonstrated that the GO‐ANI/PANI composite has a higher specific capacitance and better stability compared with GO/PANI obtained by common method. This study implies that the composite electrode could be a competitive candidate for high‐performance supercapacitor. [ABSTRACT FROM AUTHOR]