Power conversion efficiency photovoltaics

The performance of a photovoltaic cell is characterized by the power conversion efficiency r]p, which is defined by ... 

Besides ruthenium complexes, rhenium complexes were also used as the photosensitizers in photovoltaic cells. Bulk heterojunction photovoltaic cells fabricated from sublimable rhenium complexes exhibited a power conversion efficiency of 1.7%.75,76 The same rhenium complex moiety was incorporated into conjugated polymer chains such as polymer 16a c (Scheme 9). Fabrication of devices based on conjugated rhenium containing polymers 17a c and SPAN by the LbL deposition method was reported.77 The efficiencies of the devices are on the order of 10 4%. 

Photovoltaic cells with the simple device structure ITO/polymer/C6o/Al were fabricated. The power conversion efficiencies of the devices fabricated... 

Photovoltaic devices based on pure 29 and 29 PCBM blend as the active layer is fabricated. It was interesting to observe that a device with pure 29 showed a higher power conversion efficiency (0.05%) compared to that consisting of a 29/PCBM blend (0.0.0024% to 0.041%). The good performance in the photovoltaic cells with 29 only was attributed to the efficient charge separation process and that the material exhibits efficient hole and electron transport. The C6o moieties facilitated that electron transport, while the holes are transported via the hopping between Pt2-thiophene units. 

The photovoltaic properties of other Pt-acetylide polymers 31 were published by the same group (Scheme 16). The aromatic linking units were modified, and the power conversion efficiency of the devices were in the range between 0.21% and 2.66%.94 A review article dedicated to the optical properties of this group of Pt acetylide polymers has been published.95... 

The solar to electric power conversion efficiency of dye-sensitized solar cells of laboratory scale (0.158 cm2), validated by an accredited photovoltaic calibration laboratory, has reached 11.1% under standard reporting conditions, i.e., air mass 1.5 global sunlight at 1000 Wm-2 intensity and 298 K temperature, rendering it a credible alternative to conventional p-n junction photovoltaic devices [68]. Photovoltaic performance data obtained with a sandwich cell under illumination by simulated AM 1.5 solar light using complex 26 are shown in Fig. 16. At 1 sun the 26-sensitized solar cell exhibited 17.73 =b 0.5 mA current, 846 mV potential, and a fill factor of 0.75 yielding an overall conversion efficiency of 11.18%. 

Power conversion efficiency— is the ratio between output power and input power of a device. In - photovoltaic devices it denotes the ratio between the maximum electrical power supplied by a device and the incident radiant power. In this case it is given by rj = l7, " X, XFF, where Doc is the - open-circuit potential, Jsc is the - short-circuit current density, FF is the - fill factor, and E is the -y irradiance. 

Moore compared the technological branch of solar energy conversion, essentially photovoltaics, with the biological branch. He explained how a standard fuel cell that operates on oxygen and hydrogen produces water and electromotive force. A typical human-engineered fuel cell operates at 50-60 percent power conversion efficiency and uses platinum or other noble metals as catalysts. 

Power conversion efficiency (ri). Photovoltaic devices should be used for the direct conversion of sunlight to electricity. The intensity of solar radiation on the earth s surface when the sun s rays form an angle of 60° is about 691 W/m2 (AM2). The power conversion efficiency (ri) is... 

Rectification and photovoltaic effects in organic p-n junctions were first reported by Kearns and Calvin [101] and by Meier [3]. The combination of rhodamines or triphenylmethane dyes (both n-type) with merocyanines or phthalocyanines (both p-type) generated photovoltages up to 200 mV and photocurrents of about 10 8 A at low light intensity, with power conversion efficiency much less than 1%. More recent studies have been performed on merocyanine and malachite green [89,90] and on phthalocyanines and TPyP (a porphyrin derivative) [102,103]. These devices showed stronger spectral sensitization and better spectral match to a solar spectrum than those of Schottky barrier cells using only one component. 

Physical incorporatiem of phthalocyanines and porphyrins in polymers was mentioned in Chap. 2.1.1 and 2.1.2. Moreover, photovoltaic properties of Schottky bavier solar cells were checked by dispersing metal free Pc in a polymer binder At peak solar power (135 mW/cm ) a power conversion efficiency of 1,2% has been obtained. 

The photovoltaic power conversion efficiency a given operating point... 

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