Photovoltaic Device Testing

Photovoltaic devices were irradiated at 400 nm through the transparent substrate at a wavelength that gave significant absorption to determine the quantum efficiency, open voltage, and power conversion. Testing results for selected samples provided in Table 1. 

A PLED based on the fluorene-PTV copolymer 591 emitted red-orange light (02MI192). Cyano substituted poly(thienylene-viniylene-thienylene) s have been synthesized and tested for their use in photovoltaic devices and field-effect transistors (09JPS(A)4028). 

Specifically, energy- and charge-transfer properties of several different molecular-wire systems have been studied within the framework of photoinduced charge separation and solar-energy conversion. Up front, the conductance behavior of wire-like molecules was of particular interest. Such features have been carefully examined in view of possible applications in the fields of molecular electronics and/or photovoltaic devices. Among the tested systems, 7t-conjugation played a crucial role. 

The oxidative deterioration of most commercial polymers when exposed to sunlight has restricted their use in outdoor applications. A novel approach to the problem of predicting 20-year performance for such materials in solar photovoltaic devices has been developed in our laboratories. The process of photooxidation has been described by a qualitative model, in terms of elementary reactions with corresponding rates. A numerical integration procedure on the computer provides the predicted values of all species concentration terms over time, without any further assumptions. In principle, once the model has been verified with experimental data from accelerated and/or outdoor exposures of appropriate materials, we can have some confidence in the necessary numerical extrapolation of the solutions to very extended time periods. Moreover, manipulation of this computer model affords a novel and relatively simple means of testing common theories related to photooxidation and stabilization. The computations are derived from a chosen input block based on the literature where data are available and on experience gained from other studies of polymer photochemical reactions. Despite the problems associated with a somewhat arbitrary choice of rate constants for certain reactions, it is hoped that the study can unravel some of the complexity of the process, resolve some of the contentious issues and point the way for further experimentation. 

Solar Module (Panel) - A solar photovoltaic device that produces a specified power output under defined test conditions, usually composed of groups of solar cells connected In series, in parallel, or In series-parallel combinations. 

Pascal Goulpie s research team developed an awning with 4.2 m photovoltaic cells based on amorphous silicon (FlexceU). The awning s dimensions were 1.8 m X 3.8 m. The cells have been sewn on fabric from dyed acrylic [7]. The photovoltaic device was tested on the building of Industrial Services of Lausanne, Switzerland. 

PPV precmsor (Table 1) precipitated sihca and did not gel, but the silica produced did not have a well-defined structure. However, the ability of PPV to precipitate silica and not gel can be used. The precipitate can be dried and can be powdered for suitable applications in photovoltaic devices. The precipitate, when left in a test tube, was seen to change its color from white to light blue in 3-5 days and then to bluish green in 5-7 days. The conversion of the PPV precursor to PPV within the inorganic-organic hybrid system and the optical properties of this hybrid are currently being investigated. 

Test a renewables interface to a HOGEN 40 generator and collect data to understand how the system interacts with the renewable (photovoltaic- or wind-powered) device. 

The high aspect ratio of nanorods can facilitate charge transport, while the handgap can he tuned by vaiying the nanorod radius. This enables the absorption spectmm of the devices to be tailored to overlap with the solar emission spectmm, whereas traditionally polymer absorption has been limited to only a small fraction of the incident solar irradiation. At present, the nanorods in polymer solar cells are typically incorporated into a homopolymer matrix. An alternative to this approach is to incorporate the nanorods into either a polymer blend or diblock copolymer system. The photovoltaic properties of nanorod polymer composites could potentially be improved due to the percolation of nanorods, and the presence of continual electrical pathways, from the DA interfaces to the electrodes. To test this hypothesis, we use the distribution of nanorods from the self-assembled stmcture in Figure 1(b) as the input into a drift-diffusion model of polymer photovoltaics. 

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