Donor-Acceptor Complexes of Carbazole-Containing Polymers

2 Donor-Acceptor Complexes of Carbazole-Containing Polymers 

Intrinsically carbazole containing polymers are photosensitive in the UV range of spectra. The applications of such polymers in electrophotography and related processes need sensitization to the visual wavelengths. The most acceptable method is charge transfer formation between polymer donor and acceptor molecules. Hoegl pointed out that 0.1-2% of acceptor molecules inserted in the polymer matrix lead to a substantial increase in the photoconductivity especially in the CT bands. Subsequently, a lot of paper were published for CT-carbazole-containing complexes and such materials were used in photosensitive processes. Various types of molecules were used as a photosensitizers. 

Sensitized photoconductivity appears in CT bands with energy Ect 

However for the same CT complex PVC-TNF it was found that quantum efficiency had two different spectral dependence for light energy lower and above 

7 eV [17,18]. Impurity and exciton models were proposed for the photogeneration process [1,7,18,28,42]. The dependence of the quantum efficiency of the photogeneration on the electric field may be explained by the Pool-Frenkel model. The detailed analysis of the magnetic spin effects for chemical sensitization of the carbozole containing polymers was made in Ref. [49]. 

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