Graphene-based organic photovoltaics (OPVs) have the potential for single-cell efficiencies exceeding 12% (and 24% in a stacked structure). A generalized equivalent circuit for OPVs is proposed and the validation of the proposed models is verified by simulation. The simulated short-circuit photocurrent density (computed using the simulated incident photon flux density and quantum yield), simulated current-voltage curve, and simulated 3D surface and 2D contour plots of solar-power-conversion efficiency versus carrier mobility and photoactive layer thickness are in good agreement with experimental observations. The results suggest that graphene renders a credible material for the construction of next-generation flexible solar-energy-conversion devices that are low-cost, high-efficiency, thermally stable, environmentally friendly, and lightweight.

The feasibility of improving polymer composites was investigated using 30 nm SiC nanoparticles in a vinyl ester resin. Even when the particle loading was less than 4% by weight, the viscosity of the nanoparticle suspension was found to increase much higher than that of microparticle suspension. This phenomenon may be the result of association between nanoparticles and polymer molecules, effectively making the nanoparticles larger. The resulting reduction in the mobility of polymer molecules also led to delayed curing. Ultrasonic mixing did not fully disperse the particles. As a result, the composite strength did not improve although the modulus increased. The use of a dispersant, methacryloxy propyl trimethoxy silane (MPS), improved the dispersion quality and hence the composite strength. The paper discusses the issues involved with processing, characterization and properties of SiC/vinyl ester nanocomposites. Methods of improving the nanocomposite quality are proposed in the paper as well.

We developed an equivalent circuit for dye-sensitized solar cells, which provides a more accurate presentation and a better fit to the experimental I-V curves and Nyquist plots than earlier literature results, as verified by simulation. A simple expression for the estimation of the Warburg coefficient from the experimental Nyquist plot is also proposed in this letter. The simulated I-V curves and Nyquist plots are in good agreement with the experimental data. The interfacial charge transfer and recombination losses at the oxide/dye/electrolyte interface are found to be the most influential factor on the overall conversion efficiency.

We report the synthesis of graphene/fullerene-capped gold nanoparticle nanocomposite film which was used to construct supercapacitor electrodes. The fullerene-based self-assembled monolayers on gold nanoparticles (AuNPs) were attained via the fullerene (C 60)-gold interaction. The fullerene-capped AuNPs effectively separated the graphene sheets preventing aggregation. A synergistic effect was observed-the specific capacitance of graphene/fullerene-capped AuNP electrode is 197 F/g, which is higher than that of graphene electrode (31 F/g), graphene/AuNP electrode (126 F/g), and graphene/fullerene electrode (118 F/g). The results render a novel route of synthesis and modification of graphene-based materials for the construction of electrochemical energy storage devices.