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In this paper, we report on the high electrical storage capacity of composite electrodes made from nanoscale activated carbon combined with either poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) or PEDOT doped with multiple dopants such as ammonium persulfate (APS) and dimethyl sulfoxide (DMSO). The composites were fabricated by electropolymerization of the conducting polymers (PEDOT:PSS, doped PEDOT) onto the nanoscale activated carbon backbone, wherein the nanoscale activated carbon was produced by ball-milling followed by chemical and thermal treatments. Activated carbon/PEDOT:PSS yielded capacitance values of 640 F g −1 and 26 mF cm −2 , while activated carbon/doped PEDOT yielded capacitances of 1183 F g −1 and 42 mF cm −2 at 10 mV s −1. This is more than five times the storage capacity previously reported for activated carbon-PEDOT composites. Further, use of multiple dopants in PEDOT improved the storage performance of the composite electrode well over that of PEDOT:PSS. The composite electrodes were characterized for their electrochemical behaviour, structural and morphological details and electronic conductivity and showed promise as high-performance energy storage systems.

It is shown that gold nanorods (GNRs) can be easily inserted into the supramolecular order of discotic liquid crystals (DLCs) along the director without disturbing their mesomorphism. GNRs embedded discotic nanoribbons, useful for constructing devices like thin film transistors, sensors, etc., are prepared by simple solution processing of GNR-DLC nanocomposites.The self-assembling supramolecular columnar phases formed by discotic liquid crystals (DLCs) have been well recognized as onedimensional organic semiconductors useful in many devices like photovoltaic solar cells, light emitting diodes, thin film transistors, sensors, etc.1-18 On the other hand, gold nanorods (GNRs) have been extensively studied for their anisotropic properties and their applications not only in materials science but also in biosciences have been sought. 19,20 Here it is shown that GNRs can be easily inserted into the supramolecular order of DLCs without disturbing their mesomorphism. GNRs embedded discotic nanoribbons are formed simply by solution processing. These DLC-GNR nanocomposites were characterized from UV-Vis spectroscopy, transmission electron microscopy (TEM), polarizing optical microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM) and conductivity studies.Results indicate insertion of GNRs into the discotic matrix along the director (the long axis parallel to the length of the ribbon). Such supramolecular architectures are useful for constructing devices like thin film transistors, sensors, etc. Forming nanocomposites of nanoparticles with liquid crystals is an interesting field of study. Many groups have dispersed nanomaterials in the liquid crystalline system to align nanoparticles in an ordered manner while some others have functionalized nanoparticles with liquid crystalline molecules, [21][22][23][24] and also used them as optical bulk metamaterials. 25 We have previously doped the host discotics with carbonaceous, semiconducting and metallic nanoparticles and found interesting changes in their physical properties. 34 Here we show that such supramolecular triphenylene structure can be formed by a much simpler solution process. This provides an alternative to the vapour deposition technique wherein the sample has to be heated to higher temperatures, which would lead to decomposition of the organic molecules. Gold nanorods were prepared following the literature method (see ESI †) and characterized by UV-Vis spectroscopy and TEM (Fig. 1).UV-Vis spectra of gold nanorods in aqueous medium have two peaks, a small peak at 515 nm and a peak at 733 nm, which are transverse and longitudinal plasmon bands, respectively, typical of gold nanorods (Fig. 1b). 35 The band at 515 nm has a shoulder band at 581 nm, which is due to dog bone shape of gold nanorods which have slightly thicker edges compared to the middle portion. 36The TEM image of gold nanorods (Fig. 1a) shows that the nanorods prepared have an aspect ...