Bipolar transport

Bipolar transport requires both donor and acceptor functionalities. This may be accomplished by doping a polymer with separate donor and acceptor molecules, or by the use of a dopant molecule that contains both donor and acceptor functionalities. The functionalities can be either associated with a dopant molecule or incorporated within the polymer chain. Most literature references are to doped polymers where the donor and acceptor functionalities are associated with separate donor and acceptor molecules. There are few references of bipolar transport in the literature. Because of its importance to single-layer photoreceptors, however, the subject is of considerable technological relevance. 

The following section reviews bipolar transport in doped polymers of potential relevance to xerography. Discussions of molecular glasses are included as appropriate. 

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