Hybrid low resistance ultracapacitor electrodes based on 1-pyrenebutyric acid functionalized centimeter-scale graphene sheets.

Ultracapacitors are promising candidates for alternative energy storage applications since they can store and deliver energy at relatively high rates. Here, we present hybrid nanocarbon ultracapacitor electrodes with a low equivalent series resistance (ESR) of 7 ohms. 1-pyrenebutyric acid treated large-area single layer graphene (SLG) sheets covered with shortened multi-walled carbon nanotubes (MWNTs) have been utilized as highly conductive and percolated networks of hybrid carbon nanomaterial composites or thin films as ultracapacitor electrodes.

Charge carrier transport and digital data transmission performance in sub-20 nm diameter indium antimonide nanowires.

We investigated the data transmission performance of indium antimonide (InSb) nanowires synthesized on (100) type substrates using chemical vapor deposition and having diameters of 20 nm and below using the eye diagram approach of the transmission line. NW interconnect parameters including the bit error rate, quality factor, signal attenuation and maximum bandwidth have been extracted. Nanowires can sustain data rates of up to 10 mega bits per second (Mbps) without any impedance matching and de-embedding of the parasitic parameters coming from the measurement system, and the data rate is directly proportional to nanowire diameter.

Molecular absorption and photodesorption in pristine and functionalized large-area graphene layers.

We studied the photodesorption behavior of pristine and nitric acid (HNO(3)) treated graphene layers fabricated by chemical vapor deposition (CVD). The decrease in electrical conductivity and a negative shift of the Dirac point in graphene layers illuminated with ultraviolet light are caused by molecular photodesorption, while the UV illumination does not degrade the carrier mobility of graphene layers. When graphene layers were treated with concentrated HNO(3), the photodesorption-induced current decrease became less significant than for pristine graphene layers.

Label free DNA detection using large area graphene based field effect transistor biosensors.

We describe the fabrication of highly sensitive graphene based field effect transistor (FET) biosensors with a cost-effective approach and their application in label-free Deoxyribonucleic acid (DNA) detection. Chemical vapor deposition (CVD) grown graphene layers were used to achieve mass production of FET devices via conventional photolithographic patterning. Non-covalent functionalization of the graphene layer with 1-Pyrenebutanoic acid succinimidyl ester ensures high conductivity and sensitivity of the FET device.

Permanent electric dipole moments of carboxyamides in condensed media: what are the limitations of theory and experiment?

Electrostatic properties of proteins are crucial for their functionality. Carboxyamides are small polar groups that, as peptide bonds, are principal structural components of proteins that govern their electrostatic properties. We investigated the medium dependence of the molar polarization and of the permanent dipole moments of amides with different state of alkylation.

Heterogeneous graphene nanostructures: ZnO nanostructures grown on large-area graphene layers.

In this work, the synthesis and characterization of three-dimensional hetergeneous graphene nanostructures (HGN) comprising continuous large-area graphene layers and ZnO nanostructures, fabricated via chemical vapor deposition, are reported. Characterization of large-area HGN demonstrates that it consists of 1-5 layers of graphene, and exhibits high optical transmittance and enhanced electrical conductivity. Electron microscopy investigation of the three-dimensional heterostructures shows that the morphology of ZnO nanostructures is highly dependent on the growth temperature.

Synthesis of a pillared graphene nanostructure: a counterpart of three-dimensional carbon architectures.

Graphene is a single sheet of carbon atoms with outstanding electrical and physical properties and is being exploited for applications in electronics, sensors, photovoltaics, and energy storage. A novel 3D architecture called a pillared graphene nanostructure (PGN) is a combination of two allotropes of carbon, including graphene and carbon nanotubes. A one-step chemical vapor deposition process for large-area PGN fabrication via a combination of surface catalysis and in situ vapor-liquid-solid mechanisms is described.