Abstract This paper reports that the blend films of poly
(2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV)
and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis
(tetracarboxyl diimide) (EP-PDI) with the weight ratio of 1:2.5
have been prepared by spin-coating from chloroform (CF) and
chlorobenzene (CB) solutions respectively. The absorption
spectra and the morphology of the blend films show that large
crystal-like EP-PDI aggregates are formed in film prepared from
CB solution, which corresponds to a new absorption shoulder near
590nm, while there is no shoulder around 590\,nm in the
UV--Vis absorption spectra of the blend film from CF solution.
The electric-field dependence spectra of the photocurrent
generation quantum yield of the film from CB solution shows that
at weak electric field the EP-PDI aggregates act as more
efficient sensitizers, but at strong electric field the quantum
yields become almost invariable over the entire spectral range
no matter what the state of EP-PDI, monomer or aggregate. At
strong electric field, the photocurrent generation yields of
both films from CF and CB solution saturate and their yield
spectra become spectrally similar, mentioning that at strong
electric field the photoexcitons dissociate efficiently and the
free charges are collected by the electrodes almost completely.
Received: 01 December 2006
Revised: 10 December 2006
Published: 04 July 2007
Fund: Project supported by the State
Key Development Program for Basic Research of China (Grant No
2002CB613401), the National Natural Science Foundation of China
(Grant Nos 20474023 and 50673035), the Program for Changjiang
Scholars and Innovative Research Tea
Cite this article:
Zhou Yin-Hua, Yang Zhong-Feng, Wu Wei-Cai, Xia Hai-Jian, Wen Shan-Peng, Tian Wen-Jing Solvent and electric field dependence of the photocurrent generation in donor:acceptor blend system 2007 Chin. Phys. 16 2136
