We numerically analyze the optical response and nonlinear susceptibilities of fishnet metamaterials with the holes infiltrated by a third-order nonlinear dielectric. Through full-wave simulations and employing a nonlinear parameter retrieval method, we confirm and quantify the enhanced nonlinearities, showing bulk third-order nonlinear susceptibilities that are up to two orders of magnitude lar...

The most common approaches to generating power from sunlight are either photovoltaic, in which sunlight directly excites electron-hole pairs in a semiconductor, or solar-thermal, in which sunlight drives a mechanical heat engine. Photovoltaic power generation is intermittent and typically only exploits a portion of the solar spectrum efficiently, whereas the intrinsic irreversibilities of small...

Colloidal quantum dots (CQDs) offer a path toward high-efficiency photovoltaics based on low-cost materials and processes. Spectral tunability via the quantum size effect facilitates absorption of specific wavelengths from across the sun's broad spectrum. CQD materials' ease of processing derives from their synthesis, storage, and processing in solution. Rapid advances have brought colloidal qu...

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2000kg/h. Aspen Plus-based model for gasification was combined with a...

We have fabricated inverted heterojunction solar cell devices incorporating [6,6]-phenyl-C(61)-butyric acid methyl ester/poly(3-hexylthiophene) core/shell nanorod arrays by using an anodic alumina oxide template. The internal quantum efficiencies and external quantum efficiencies of these core/shell nanorod inverted solar cells were higher than those of the corresponding conventional inverted b...

We evaluate practical power conversion efficiency limits lim in bulk-heterojunction organic photovoltaic BHJ OPV cells and how the field dependence of exciton dissociation affects cell efficiencies. We treat the fill factor limit as a function of the donor-acceptor lowest unoccupied molecular orbital offset energy ELLO , calculating how this limit varies with decreasing ELLO. We also evaluate O...

CH3NH3PbX3 (MAPbX3) perovskites have attracted considerable attention as absorber materials for solar light harvesting, reaching solar to power conversion efficiencies above 20%. In spite of the rapid evolution of the efficiencies, the understanding of basic properties of these semiconductors is still ongoing. One phenomenon with so far unclear origin is the so-called hysteresis in the current-...

The effect of reaction temperature on the synthesis of graphitic thin film on nickel substrate was investigated in the range of 400°C to 1,000°C. Amorphous carbon (a-C) film was obtained at 400°C on nickel foils by chemical vapor deposition; hybrid films of multilayer graphene (MLG) and a-C were synthesized at a temperature of 600°C, while MLG was obtained at temperatures in excess of 800°C. Sc...

The effects of using different counter electrode metal sulfides on the performances of solar cells made with CdS/CdSe/ZnS quantum dots co-sensitized onto hierarchical TiO2 spheres (HTSs) used as photo-electrode are reported. The HTS in the QDSSCs is composed of an assembly of numerous TiO2 spheres made by the solvolthermal method. The photoelectrical performance of HTS/CdS/CdSe/ZnS coupled to C...

162 nature photonics | VOL 6 | MARCH 2012 | www.nature.com/naturephotonics Dye-sensitized solar cells (DSCs) are attractive because they are made from cheap materials that do not need to be highly purified and can be printed at low cost1. DSCs are unique compared with almost all other kinds of solar cells in that electron transport, light absorption and hole transport are each handled by differ...