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Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton
Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton
Gordon Wallace
Aqueous dispersions of reduced graphene oxide (rGO) and multi walled carbon nanotubes (MWCNT) were fabricated through a modified chemical reduction method. The significant advantage of the method developed here is the omission of any stabilising compound or organic solvent to obtain stable rGO-MWCNT dispersions. Significantly biological entities, in this case the enzyme glucose oxidase (GOx), can be successfully incorporated into the dispersion. These dispersions were characterised using XPS, SEM, zeta potential and particle size measurements which showed that the dispersion stability is not sacrificed with the addition of GOx, and significantly, the electrical properties of the rGO and MWCNTs are …
Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace
Facile Synthesis Of Reduced Graphene Oxide/Mwnts Nanocomposite Supercapacitor Materials Tested As Electrophoretically Deposited Films On Glassy Carbon Electrodes, Widsanusan Chartarrayawadee, Simon E. Moulton, Chee O. Too, Byung C. Kim, Rao Yepuri, Anthony C. Romeo, Gordon G. Wallace
Gordon Wallace
This paper reports on a facile synthesis method for reduced graphene oxide (rGO)/multi-walled carbon nanotubes (MWNTs) nanocomposites. The initial step involves the use of graphene oxide to disperse the MWNTs, with subsequent reduction of the resultant graphene oxide/MWNTs composites using l-ascorbic acid (LAA) as a mild reductant. Reduction by LAA preserves the interaction between the rGO sheets and MWNTs. The dispersion-containing rGO/MWNTs composites was characterized and electrophoretically deposited anodically onto glassy carbon electrodes to form high surface area films for capacitance testing. Pseudo capacitance peaks were observed in the rGO/MWNTs composite electrodes, resulting in superior performance with capacitance values up …
Scalable One-Step Wet-Spinning Of Graphene Fibers And Yarns From Liquid Crystalline Dispersions Of Graphene Oxide: Towards Multifunctional Textiles, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Roderick L. Shepherd, Jun Chen, Sima Aminorroaya-Yamini, Konstantin Konstantinov, Andrew I. Minett, Joselito M. Razal, Gordon G. Wallace
Scalable One-Step Wet-Spinning Of Graphene Fibers And Yarns From Liquid Crystalline Dispersions Of Graphene Oxide: Towards Multifunctional Textiles, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Roderick L. Shepherd, Jun Chen, Sima Aminorroaya-Yamini, Konstantin Konstantinov, Andrew I. Minett, Joselito M. Razal, Gordon G. Wallace
Gordon Wallace
Key points in the formation of liquid crystalline (LC) dispersions of graphene oxide (GO) and their processability via wet-spinning to produce long lengths of micrometer-dimensional fibers and yarns are addressed. Based on rheological and polarized optical microscopy investigations, a rational relation between GO sheet size and polydispersity, concentration, liquid crystallinity, and spinnability is proposed, leading to an understanding of lyotropic LC behavior and fiber spinnability. The knowledge gained from the straightforward formulation of LC GO "inks" in a range of processable concentrations enables the spinning of continuous conducting, strong, and robust fibers at concentrations as low as 0.075 wt%, eliminating …
Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen
Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen
Gordon Wallace
By controlling the SWNT-rGO electrode composition and thickness to attain the appropriate porosity and tortuosity, the electroactive surface area is maximized while rapid diffusion of the electrolyte through the electrode is maintained. This leads to an increase in exchange current density between the electrode and electrolyte which results in enhanced thermocell performance.
Organic Solvent-Based Graphene Oxide Liquid Crystals: A Facile Route Toward The Next Generation Of Self-Assembled Layer-By-Layer Multifunctional 3d Architectures, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Konstantin Konstantinov, Simon E. Moulton, Joselito M. Razal, Gordon G. Wallace
Organic Solvent-Based Graphene Oxide Liquid Crystals: A Facile Route Toward The Next Generation Of Self-Assembled Layer-By-Layer Multifunctional 3d Architectures, Rouhollah Jalili, Seyed Hamed Aboutalebi, Dorna Esrafilzadeh, Konstantin Konstantinov, Simon E. Moulton, Joselito M. Razal, Gordon G. Wallace
Gordon Wallace
We introduce soft self-assembly of ultralarge liquid crystalline (LC) graphene oxide (GO) sheets in a wide range of organic solvents overcoming the practical limitations imposed on LC GO processing in water. This expands the number of known solvents which can support amphiphilic self-assembly to ethanol, acetone, tetrahydrofuran, N-dimethylformamide, N-cyclohexyl-2-pyrrolidone, and a number of other organic solvents, many of which were not known to afford solvophobic self-assembly prior to this report. The LC behavior of the as-prepared GO sheets in organic solvents has enabled us to disperse and organize substantial amounts of aggregate-free single-walled carbon nanotubes (SWNTs, up to 10 wt …
Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen
Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen
Gordon Wallace
Graphene based materials coupled with transition metal oxides are promising electrode materials in asymmetric supercapacitors owing to their unique properties which include high surface area, good chemical stability, electrical conductivity, abundance, and lower cost profile over time. In this paper a composite material consisting of graphene oxide exfoliated with microwave radiation (mw rGO), and manganosite (MnO) is synthesised in order to explore their potential as an electrode material. The composite material was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to explore …
Cation Exchange At Semiconducting Oxide Surfaces: Origin Of Light-Induced Performance Increases In Porphyrin Dye-Sensitized Solar Cells, Matthew J. Griffith, Kenji Sunahara, Akihiro Furube, Attila J. Mozer, David L. Officer, Pawel Wagner, Gordon G. Wallace, Shogo Mori
Cation Exchange At Semiconducting Oxide Surfaces: Origin Of Light-Induced Performance Increases In Porphyrin Dye-Sensitized Solar Cells, Matthew J. Griffith, Kenji Sunahara, Akihiro Furube, Attila J. Mozer, David L. Officer, Pawel Wagner, Gordon G. Wallace, Shogo Mori
Gordon Wallace
The origin of simultaneous improvements in the short-circuit current density (Jsc) and open-circuit voltage (Voc) of porphyrin dye-sensitized TiO2 solar cells following white light illumination was studied by systematic variation of several different device parameters. Reduction of the dye surface loading resulted in greater relative performance enhancements, suggesting open space at the TiO2 surface expedites the process. Variation of the electrolyte composition and subsequent analysis of the conduction band potential shifts suggested that a light-induced replacement of surface-adsorbed lithium (Li+) ions with dimethylpropylimidazolium (DMPIm+) ions was responsible for an increased electron lifetime by decreasing the recombination with the redox mediator. …