New methodologies connecting molecular structure, self-organization, and nanoelectronics are important for the construction of better bulk heterojunction solar cells. In the present work, large area conjugated polymer honeycomb thin films were prepared from poly {2, 5-bis [3-N, N-diethylamino)-1-oxapropyl]-1, 4-phenylenevinylene} (P1) and EG-C60 (1:1 wt/wt). Further, surface morphology and conductivity of honeycomb thin films were studied using conductive-atomic force microscopy. The morphological studies clearly confirm that the EG-C60 molecules are uniformly present only at the nodes and frames of honeycomb structured blend film (which avoids the formation of exciton pair recombination of polymer), whereas the TUNA current map collected at positive and negative biases reveal holes and electrons collection networks corresponding to donor and acceptor phases at honeycomb thin films. This discovery could find applications in fully exploiting the potential of various material systems, and may open up new opportunities to improve the efficiency of organic solar cells.
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See supplementary material at http://dx.doi.org/10.1063/1.4945007 for the details of materials and device fabrication for C-AFM study.
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