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Bulk quantities of electronic conducting polymers such as polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene) exhibiting an unusual 2D nanoclip-like morphology are described. The polymers designed by using a general oxidative template assembly route are orchestrated by an insoluble complex formed between an anionic oxidant ([S.sub.2][O.sub.8.sup.2-]) and a cationic surfactant.

Nanofibers of polyanilineand oligoanilines of controlled molecular weight are prepared by using high ionic strength aqueous system that has permitted the use of [H.sub.2][O.sub.2] with no added catalysts as a mild oxidizing agent. The films of oligoanilines deposited on plastic substrates have displayed a robust and reversible chemiresistor response to N[O.sub.2] vapor at room temperature in ambient air.

A study reveals that the absolute weights of parent polyaniline bases in the pernigraniline, emeraldine, and leucoemeraldine oxidation states are measured by light scattering and the exact number of aniline repeat units determined. It is concluded that the absolute molecular weight of parent polyaniline in all three isolable oxidation states, synthesized at three different temperatures.

We report an in situ measurement of the interaction of an imidazolium-based room temperature ionic liquid with both pure silver and a graphene-over-silver electrode under an applied electrochemical potential. At a negative applied potential, overall signal intensity increased indicating enhanced ionic liquid concentration at both silver and graphene electrodes. Vibrational modes associated with the imidazolium ring exhibited greater intensity enhancements and larger peak shifts compared with the anion indicating that the cation adsorbs with the ring and alkyl chain parallel to the electrode surface for both silver and graphene. In contrast to the silver, the surface enhanced Raman spectra of the ionic liquid near graphene showed shifts in the cation peaks even at no applied potential because of the strong π-π interaction between the ionic liquid and the graphene. Furthermore, the intensity of the graphene peak decreased in the presence of ionic liquid possibly due to the interaction between the ionic liquid and graphene. These results illustrate the effectiveness of surface-enhanced Raman spectroscopy to investigate electrolyte interactions with graphene at the liquid/electrode interface. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

High electrochemical reactivity is required for various energy and sensing applications of graphene grown by chemical vapor deposition (CVD). Herein, we report that heterogeneous electron transfer can be remarkably fast at CVD-grown graphene electrodes that are fabricated without using the conventional poly(methyl methacrylate) (PMMA) for graphene transfer from a growth substrate. We use nanogap voltammetry based on scanning electrochemical microscopy to obtain very high standard rate constants k0 ≥ 25 cms-1 for ferrocenemethanol oxidation at polystyrene-supported graphene. The rate constants are at least 2-3 orders of magnitude higher than those at PMMA-transferred graphene, which demonstrates an anomalously weak dependence of electrontransfer rates on the potential. Slow kinetics at PMMAtransferred graphene is attributed to the presence of residual PMMA. This unprecedentedly high reactivity of PMMA-free CVD-grown graphene electrodes is fundamentally and practically important. [ABSTRACT FROM AUTHOR]

Rechargeable Li-ion batteries (LIBs) are currently the dominant power source for portable electronic devices and electric vehicles, and for small-scale stationary energy storage. However, one bottleneck of the anode materials for LIBs is the poor cycling performance caused by the fact that the anodes cannot maintain their integrity over several charge–discharge cycles. In this work, we demonstrate an approach to improving the cycling performance of lithium-ion battery anodes by constructing an extended 3D network of flexible redox active polyoxometalate (POM) clusters with redox active organic linkers, herein described as POMOF. This architecture enables the accommodation of large volume changes during cycling at relatively high current rates. For example, the POMOF anode exhibits a high reversible capacity of 540 mA h g−1 after 360 cycles at a current rate of 0.25C and a long cycle life at a current rate of 1.25C (＞500 cycles). [ABSTRACT FROM AUTHOR]

Wereport the effect of chemical and physical treatments on thestructural stability of DNA origami nanostructures. Our result showsthat DNA nanostructure maintains its shape under harsh processingconditions, including thermal annealing up to 200 °C for 10 min,immersing in a wide range of organic solvents for up to 24 h, briefexposure to alkaline aqueous solutions, and 5 min exposure to UV/O3. Our result suggests that the application window of DNA nanostructureis significantly wider than previously believed. [ABSTRACT FROM AUTHOR]

We demonstrate a new approach to pattern transfer for bottom-up nanofabrication. We show that DNA promotes/inhibits the etching of SiO2 at the single-molecule level, resulting in negative/positive tone pattern transfers from DNA to the SiO2 substrate. [ABSTRACT FROM AUTHOR]

The article presents the study that demonstrated that synthesis of catalyst-free synthesis of oligoanilines and polyaniline nanofibers using H2O2. The study demonstrated the synthesis of bulk quantities of polyaniline nanofibers using H2O2 oxidant without added catalyst. It also revealed the synthesis of oligoanilines of controlled molecular weight using H2O2.

Bulk quantities of parent polythiophene nanofibers can be synthesized rapidly and in one step by chemical oxidative polymerization of thiophene by FeCl3 using freeze-dried vanadium pentoxide nanofibers as seeds. [ABSTRACT FROM AUTHOR]

High electrochemical reactivity is required for various energy and sensing applications of graphene grown by chemical vapor deposition (CVD). Herein, we report that heterogeneous electron transfer can be remarkably fast at CVD-grown graphene electrodes that are fabricated without using the conventional poly(methyl methacrylate) (PMMA) for graphene transfer from a growth substrate. We use nanogap voltammetry based on scanning electrochemical microscopy to obtain very high standard rate constants k(0) ≥25 cm s(-1) for ferrocenemethanol oxidation at polystyrene-supported graphene. The rate constants are at least 2-3 orders of magnitude higher than those at PMMA-transferred graphene, which demonstrates an anomalously weak dependence of electron-transfer rates on the potential. Slow kinetics at PMMA-transferred graphene is attributed to the presence of residual PMMA. This unprecedentedly high reactivity of PMMA-free CVD-grown graphene electrodes is fundamentally and practically important., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)