The well-known electro-mechanical analogy that equates current, voltage, resistance, inductance and capacitance to force, velocity, damping, spring constant and mass has a shortcoming in that mass can only be used to simulate a capacitor which has one terminal connected to ground. A new model that was previously proposed by the authors that combines a mass with a pulley (MP) is shown to simulat...

A novel class of micro-electrodes was fabricated by synthesizing high density carbon nanotube islands on lithographically defined, passivated titanium nitride conductors on a silicon dioxide substrate. Electrochemical characterization in phosphate buffered saline of these new electrodes reveals superb electrochemical properties marked by featureless rectangular cyclic voltammetry curves corresp...

An efficient active material for supercapacitor electrodes is prepared by reacting potassium hydroxide (KOH) with graphene oxide followed by chemical reduction with hydrazine. The electrochemical performance of KOH treated graphene oxide reduced for 24 h (reduced chemically modified graphene oxide, RCMGO-24) exhibits a specific capacitance of 253 F g(-1) at 0.2 A g(-1) in 2 M H2SO4 compared to ...

A porous nanocomposite based on polypyrrole (PPy) and sodium alginate (SA) has been synthesized by easy, inexpensive, eco-friendly method. As prepared nanocomposite showed fibrillar morphology in transmission electron microscopic (TEM) analysis. The average diameter of ~100 nm for the nanofibers was observed from scanning electron microscopic (SEM) analysis. As prepared nanofiber, was investiga...

2-Aminoanthraquinone (AAQ) molecules were covalently grafted onto chemically modified graphene (CMG), and the AAQ functionalized CMG sheets were self-assembled into macroporous hydrogels for supercapacitor electrodes. The electrode based on the AAQ modified self-assembled graphene hydrogel (AQSGH) showed a high specific capacitance of 258 F g(-1) at a discharge current density of 0.3 A g(-1), w...

The poor cycling stability of polyaniline (PANI) limits its practical application as a pseudocapacitive material due to the volume change during the charge-discharge procedure. Herein, crosslinked carbon nanotubes/polyaniline (C-CNTs/PANI) composites had been designed by the in situ chemical oxidative polymerization of aniline in the presence of crosslinked carbon nanotubes (C-CNTs), which were...

Uniform PNHCF-NPs were prepared by co-precipitation way and coated on carbon cloth for high-performance supercapacitor applications. The hybrid showed highly flexible, improved specific capacitance, good stability in Na + K ion electrolytes.

Differential capacitance versus frequency curves simulated for different equivalent circuits representing different cases of anion adsorption have been analyzed. The analysis showed that in all cases with an ideal, homogeneous electrode surface, the real value of the differential capacitance, representing the sum of the double layer and adsorption capacitances (independent of frequency) could b...

We have built a physical gate capacitance model for III-V FETs that incorporates quantum capacitance and centroid capacitance in the channel. We verified its validity with simulations (Nextnano) and experimental measurements on High Electron Mobility Transistors (HEMTs) with InAs and InGaAs channels down to 30 nm in gate length. Our model confirms that in the operational range of these devices,...

Carbon nanotubes uniformly 50 nm in diameter were directly grown on graphite foil. Cyclic voltammetry (CV) shows that the carbon nanotube /graphite foil electrode has a high specific capacitance (115.7 F/g at a scan rate of 100 mV/s) and exhibits typical double-layer behavior. A rectangular-shaped CV curve persists even at a scan rate of 100 mV/s in 1.0 M H SO aqueous solution, which suggests t...