Photoconductivity of poly((E,E)-[6.2]paracyclophane-1,5-diene) doped with low molecular weight acceptors

Poly((E,E)-[6.2]paracyclophane-1,5-diene) (PDE) exhibits high hole mobility due to a cofacial alignment of bridged aromatic rings, but it shows low photoconductivity. After sensitization with low molecular weight acceptors, the photoconductivity increases considerably. In a series of PDE doped with several benzoquinone derivatives it was found that with an increase of electron affinity of the dopant, the spectral sensitivity extends more into visible range. In the system showing the highest photoconductivity, PDE with 2,4,7-trinitrofluorenone, the maximum of the photoconductivity gain spectrum correlates with the charge-transfer absorption band. Strong field dependence of the photoconductivity gain is a consequence of field-dependences of both photogeneration and mobility