@article { ISI:000233825900101, title = {Enhancement of double-layer capacitance behavior and its electrical conductivity in layered poly (3, 4-ethylenedioxythiophene)-based nanocomposites}, journal = {Applied Physics Letters}, volume = {87}, number = {24}, year = {2005}, month = {DEC}, pages = {243511}, publisher = {AMER INST PHYSICS}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

In this letter, we report on the enhanced double-layer capacitance of a layered poly (3, 4-ethylene dioxythiophene) PEDOT-MoO3 nanocomposite, which has been synthesized by a novel microwave irradiation method. The x-ray photoelectron spectroscopy analysis shows the changes in electron density and the shift in binding energy suggesting charge transfer from sulfur atoms upon PEDOT intercalation between MoO3 layers. The room-temperature conductivity for the PEDOT-MoO3 composite is found to be 1.82x10(-1) S cm(-1), which is four orders of magnitude higher than that of the pristine oxide (3.78x10(-5) S cm(-1)). The enhanced double-layer capacitance of the PEDOT-MoO3 nanocomposite (similar to 300 F g(-1)) compared to that (similar to 40 mF g(-1)) of pristine MoO3 is attributed to higher electronic conductivity, enhanced bidimensionality, and increase in surface area of the nanocomposite.

}, issn = {0003-6951}, doi = {10.1063/1.2140468}, author = {Murugan, A. Vadivel and Viswanath, A. K. and Campet, Guy and Gopinath, Chinnakonda S. and Vijayamohanan, K.} } @article { ISI:000226995900011, title = {Entrapment of poly(3,4-ethylenedioxythiophene) between VS2 layers to form a new organic-inorganic intercalative nanocomposite}, journal = {Journal of Materials Chemistry}, volume = {15}, number = {8}, year = {2005}, month = {JAN}, pages = {902-909}, publisher = {ROYAL SOC CHEMISTRY}, type = {Article}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Here we report the synthesis and characterization of a new class of nanocomposite by direct in situ oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) with VS2 as a host material in the presence of an external oxidizing agent. Upon intercalation, the interlayer spacing of VS2 expands from 5.71 Angstrom to 14.01 Angstrom, followed by exfoliation and a restacking process facilitating expansion of the lattice in a direction perpendicular to the dichalcogenide layers. This change in interlayer separation is consistent with the existence of two phases of organic and inorganic species in the nanocomposites corresponding to the intercalation of PEDOT in the VS2 framework. The resulting nanocomposite is characterized by thermal analysis (TGA), X-ray diffraction, FTIR, SEM, TEM, and four-probe electrical conductivity measurements. The application potential of the nanocomposite as a cathode material for rechargeable lithium batteries is also demonstrated by the electrochemical intercalation of lithium into the PEDOT-VS2 nanocomposite, where a significant enhancement in the discharge capacity is observed (similar to130 mA h g(-1)) compared to that (80 mA h g(-1)) for pristine VS2.

}, issn = {0959-9428}, doi = {10.1039/b414922j}, author = {Murugan, A. Vadivel and Quintin, M. and Delville, M. H. and Campet, Guy and Vijayamohanan, K.} } @article { ISI:000238412100062, title = {Exfoliation-induced nanoribbon formation of poly(3,4-ethylene dioxythiophene) PEDOT between MoS2 layers as cathode material for lithium batteries}, journal = {Journal of Power Sources}, volume = {156}, number = {2}, year = {2006}, month = {JUN}, pages = {615-619}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A new type of layered nanocomposite synthesized by delaminated MoS2 nanosheets and poly(3,4-ethylenedioxythiophene) (PEDOT) are restacked to produce alternate polymer nanoribbons between layers Of MoS2 with an interlayer distance of similar to 1.38 nm. The unique properties of resulting nanocomposite are investigated by powder XRD, XPS, SEM, TEM, and four-probe conductivity measurements. The obtained nanocomposite can be used as a cathode material for a small power rechargeable lithium battery as demonstrated by the electrochemical insertion of lithium into the PEDOT/MoS2 nanocomposite. A significant enhancement in the discharge capacity (100 mAh g(-1)) is observed compared with that (40 mAh g(-1)) for MoS2. (c) 2005 Elsevier B.V All rights reserved.

}, keywords = {cathode material, lithium batteries, MoS2, organic-inorganic nanocomposite, PEDOT-nanoribbons}, issn = {0378-7753}, doi = {10.1016/j.jpowsour.2005.06.022}, author = {Murugan, A. Vadivel and Quintin, M. and Delville, M. H. and Campet, Guy and Gopinath, Chinnakonda S. and Vijayamohanan, K.} } @article { ISI:000246329700015, title = {Cyclic voltammetry, electrochemical impedance and ex situ X-ray diffraction studies of electrochemical insertion and deinsertion of lithium ion into nanostructured organic-inorganic poly(3,4-ethylenedioxythiophene) based hybrids}, journal = {Journal of Electroanalytical Chemistry}, volume = {603}, number = {2}, year = {2007}, month = {MAY}, pages = {287-296}, publisher = {ELSEVIER SCIENCE SA}, type = {Article}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

In this work, we discuss the electrochemical insertion and deinsertion of lithium into poly(3,4-ethylenedioxythiophene) PEDOT-V(2)O(5) nanohybrids by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and powder ex situ X-ray diffraction (XRD) studies with special emphasis on their application potential as cathode materials for rechargeable Lithium batteries. The interlayer spacing of crystalline V(2)O(5) expands from 0.43 to 1.41 nm by the intercalation of PEDOT nanoribbons prepared by a microwave irradiation method. Cyclic voltammetry studies of PEDOT-V(2)O(5) hybrid at a slow scan rate of 0.058 mVs(-1) between 2.0-4.3 V vs. Li/ Li(+), demonstrates that structural transitions Of V(2)O(5) are suppressed and more facile intercalation features appear in terms of well-defined reversible cathodic and anodic peaks when compared to that at higher scan rate. Electrochemical Impedance studies of PEDOT-V(2)O(5) hybrid as cathode at ambient temperature with lithium metal foil as both counter and reference electrodes in 1 M LiPF(6) in a mixture of ethylene and diethylcarbonate (50:50 by volume) between the range 2.0-4.3 V reveals the usefulness of these materials. The observed capacity fading during cycling in terms of surface passivation and structural transformations is also investigated by CV, EIS and XRD analysis. (C) 2007 Elsevier B.V. All rights reserved.

}, keywords = {cyclic voltammetry, ex situ XRD studies, high capacity lithium batteries, impedance studies, nanostructured hybrid materials}, issn = {1572-6657}, doi = {10.1016/j.jelechem.2007.02.013}, author = {Murugan, A. Vadivel and Reddy, M. V. and Campet, Guy and Vijayamohanan, K.} }