Compositions solar control

Solar control compositions are composed of an infrared absorbing phthalocyanine, naphthalocyanine, and an ionomer (17). 

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. 

For photochemical aging, it is well known that photooxidation affects only a thin superficial layer directly exposed to solar radiation - a few dozens of micrometers in the case of epoxies (Bellenger and Verdu, 1983). Thus the aging mode cannot control the material s lifetime in most cases (composites, adhesives), except for applications such as, for example, varnishes of automotive bodies (Bauer et ah, 1992). 

Self-assembled and spontaneously adsorbed monolayers offer a facile means of controlling the chemical composition and physical structure of a surface. As discussed later in Chapter 5, applications of these monolayers include modeling election transfer reactions, biomimetic membranes, nano-scale photonic devices, solar energy conversion, catalysis, chemical sensing and nano-scale lithography. 

One of the substrates that deserves special attention in our discussion is silicon (Si), and in particular Si wafers for producing solar cells. A variety of sirrface treatments are applied to Si in the solar cell industry Native Si vs. chemically protected (SiN, for example), pohshed versus unpohshed versus patterned to give surface texture, etc. In order to ensirre proper Si-metal contacts, careful control of the conductive ink composition is required. In addition, very high curing temperatures are usually employed in the manufacture of solar cells, thus there is a need for a suitable binding component. Special care is taken to avoid excessive diffusion of metal into the emitter layer, nevertheless, somewhat limited diffusion is desirable so that contact resistance is adequate. ... 

Erosion. Reactions involving hyperthermal collisions of O atoms with various polymeric surfaces (e.g. optical and thermal control coatings, carbon-based composites, thermal blankets, solar panels, optical components) lead to the production of volatile reaction products, which carry mass... 

Quantitative evaporation experiments using solar system and solar system-like materials were pioneered by Hashimoto (1983, 1990) in terms of chemical fractionations and by Davis et al. (1990) in terms of the isotopic fractionation of the evaporation residues. Quantitative condensation experiments are much more difficult, and there are no well-controlled condensation experiments available on chondritic or CAl compositions. The compositions that have been most extensively smdied in evaporation experiments intended for application to the solar system are pure forsterite (Mg2Si04), a type B CAI-like liquid consisting of CaO, MgO, AI2O3, and Si02, and a liquid in which major oxides including those of iron are initially in solar proportions. 

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