Photovoltaic sandwich cells power conversion

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%. 

Quite pronounced photovoltaic effects have been observed in Mx 1150 nm -chlorophyll a M2 sandwich cells, where Mx = A1 or Cr and M2 = Hg or Au.7e>77 These are ascribed to a Schottky barrier at the junction with metal Mx which has a lower work function than M2. If the Mi junction is the front (illuminated) electrode then the photovoltaic action spectrum is identical with the absorption spectrum of the chlorophyll. If it is at the rear, the action spectrum shows an inner filter effect, because only light absorbed in the region of the barrier is effective. Figure 11 shows the performance of a typical cell, which has a power conversion efficiency of ca. 10-3% at 745 nm. The best efficiency, 5 x 10-a%, was achieved by a Cr chlorophyll a Hg cell. Photovoltaic properties have also been reported in the cell A11 Mg phthalocyanine Ag, which has a Schottky barrier of height ca. 0.6 eV at the A1 junction.78 At 690 nm, the power conversion efficiency was ca. 10-2%. It has been shown that oxidized A1 contacts to Cu phthalocyanine are blocking.79... 

Various other polymer films can form solid-state cells. Al/poly(p-phenylenesulfide) (27, PPS)/Cu cell exhibited Vo5 = 0.5VandJje = 1.8 nAcm under monochromatic light of 300 nm with a conversion efficiency of 0.21 % Electrochemically doped poly(V-vinylcarbazole) showed a photovoltaic effect when sandwiched between A1 and gold (Au) electrodes Voc = 101 V, Jj, = 182 nA cm , and FF = 0.237 were reported. The power conversion efficiency was 2.8 x 10" % under 1.08 mW cm monochromatic light. Complexes of poly(ethylene oxide) with sodium polyiodide formed a photovoltaic cell when sandwiched between ITO and Pt... 

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