Field solar cells

H. Field, Solar Cell Spectral Response Measurements Related to Spectral Bandwidth and Chopped Light Waveform, 26th IEEE Photovoltaic Specialists Conference, Institute of Electrical and Electronic Engineers, Anaheim, CA, 1997. 

H. Field Solar cell spectral response measurement errors related to spectral band width and chopped light waveform, in Proceedings of the 26th IEEE Photovoltaic Specialists Conference, 1209-1212 (1997)... 

Recently, room temperature ionic liquids (RT-ILs) have attracted much attention for their excellent properties, e.g., wide temperature range of liquid phase, ultra-low vapor pressure, chemical stability, potential as green solvents, and high heat capacities [64,65]. These properties make them good candidates for the use in many fields, such as thermal storage [66], electrochemical applications, homogeneous catalysis [67], dye sensitized solar cells [68], and lubricants [69,70]. 

Given the actual scenario, one can state that the emerging field of nanotechnology represents new effort to exploit new materials as well as new technologies in the development of efficient and low-cost solar cells. In fact, the technological capabilities to manipulate matter under controlled conditions in order to assemble complex supramolecular structures within the range of 100 nm could lead to innovative devices (nano-devices) based on unconventional photovoltaic materials, namely, conducting polymers, fuUerenes, biopolymers (photosensitive proteins), and related composites. 

In any case, it is perceived from the above discussion that the problem of longterm chemical stability of polycrystalline semiconductor liquid junction solar cells is far from being solved. Still, as already pointed out in the early research, any practical photovoltaic and PEC device would have to be based on polycrystalline photoelectrodes. Novel approaches mostly involving specially designed PEC systems with alternative solid or gel electrolytes and, most importantly, hybrid/sensitized electrodes with properties dictated by nanophase structuring - to be discussed at the end of this chapter - promise new advances in the field. 

In the presence of an electric field the drift length is the mobility-lifetime product times the electric field A.mfp = prE [576]. With typical values of pz and E the mean free path usually exceeds by far the thickness of the solar cell, and virtually all photogenerated carriers can be collected. However, under certain operating conditions, field-free regions in the / -layer may exist, and the collection efficiency is decreased because the diffusion lengths of the carriers are much smaller than the thickness of the solar cell [11, 577]. 

Poly-(acetylene)s are widely used in different fields, such as organic light-emitting diodes (OLEDS), solar cells, and lasers.135 Synthesis... 

The chapters cover the following areas (i) use of coordination complexes in all types of catalysis (Chapters 1-11) (ii) applications related to the optical properties of coordination complexes, which covers fields as diverse as solar cells, nonlinear optics, display devices, pigments and dyes, and optical data storage (Chapters 12-16) (iii) hydrometallurgical extraction (Chapter 17) (iv) medicinal and biomedical applications of coordination complexes, including both imaging and therapy (Chapters 18-22) and (v) use of coordination complexes as precursors to semiconductor films and nanoparticles (Chapter 23). As such, the material in this volume ranges from solid-state physics to biochemistry. 

As a class of n-type organic semiconductors, PBI derivatives have received considerable attention for a variety of applications [312, 313], for example, for organic or polymer light-emitting diodes (OLEDs and PLEDs) [314, 315], thin-film organic field-effect transistors (OFETs) [316, 317], solar cells [318, 319], and liquid crystals [320]. They are also interesting candidates for single-molecule device applications, such as sensors [321], molecular wires [322], or transistors [141]. 

Because of its indirect bandgap, bulk crystalline silicon shows only a very weak PL signal at 1100 nm, as shown for RT and 77 K in Fig. 7.9. Therefore optoelectronic applications of bulk silicon are so far limited to devices that convert light to electricity, such as solar cells or photodetectors. The observation of red PL from PS layers at room temperature in 1990 [Cal] initiated vigorous research in this field, because efficient EL, the conversion of electricity into light, seemed to be within reach. Soon it was found that in addition to the red band, luminescence in the IR as well as in the blue-green region can be observed from PS. 

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