Photoconductor oxidation

Metal chelates of 8-hydroxyquinoline such as (111) with photoconductive properties are reported to be useful in electrophotographic systems.233 The incorporation of a tin complex into a photo-conductive zinc oxide layer is stated to reduce dark decay . In other words, the electrostatic charge applied to the photoconductor has a longer lifetime. Two of the complexes disclosed for this application are (112) and (113). These compounds are prepared from dibutyltin oxide by reaction with 2-mercaptopropionic add and thioglycolic acid, respectively 234... 

An inorganic photoconductor such as zinc oxide can be optically sensitized by treating it with a ligand that will form a colored zinc complex. The resulting material then responds to light of the wavelength where the complex absorbs. Suitable ligands are prepared by the condensation of heterocyclic hydrazines and heterocyclic aldehydes.235 Two examples of the more than 50 disclosed in the patent literature are (114) and (115). 

The geometry we use is shown in Fig. 20a. A semitransparent conductor, a photoconductor, a second semitransparent conductor, and a polymer film are successively deposited on a glass substrate. The semitransparent conductors are about 10-nm-thick layers of Nb deposited by ion-beam sputtering. Although the films have an optical density of—0.25, they are very stable and easy to contact. More transparent conductors, such as indium-tin-oxide, can be used if the subsequent processing temperature remains below 250°C. 

Zinc oxide Photoconductor device coatings, piezoelectric devices. 

Anthracene and phenanthrene are stereoisomers that are crystals in pure form. Anthracene is a pale yellow crystal, while phenanthrene exhibits a yellow to brown hue. Besides its common name, anthracene is referred to as anthracin, green oil, or paranaphthalene. The compound is commercially produced by recovery from the coal tar distillation fraction known as anthracene oil or green oil. Anthracene is the key ingredient in the production of anthraquinone. However, it and phenanthrene are also used for the manufacture of dyes, fibers, plastics, and wood preservatives. ° Phenanthrene, also known as phenanthrin, can be produced by high-temperature fractional distillation of coal tar oil. It is additionally used for the oxidation of diphenic acid for use in polymers, as well as the production of chemical softeners, explosives, and some pharma-ceuticals. Recent research has extended the application of both isomers to scintillation counters, semiconductors, and photoconductors. ... 

Therefore, the photoconductor must not only be free of thermal carriers but it must be protected against the dark injection of external charge, as well. Injection from the base electrode may be avoided by a thin blocking dielectric—typically 50 A.U. of a dense oxide or polymer--thin enough to allow any accumulated residual charge to leak off between cycles. 

Zinc oxide also illustrates one further interaction. Since this photoconductor intrinsically only responds to ultraviolet radiation, it is commonly sensitized to visible light by the adsorption of a monolayer of one or more dyes (Figure 7). This adds yet another essential interface to an already complex system (37-40). 

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