Characterization of the Photoactive Layer Electron Tomography

Volume Characterization of the Photoactive Layer Electron Tomography 

The performance of PSCs strongly depends, as stated above, on the three-dimensional organization of the compounds within the photoactive layer. Donor and acceptor materials should form co-continuous networks with nanoscale phase separation to be able to effectively dissociate exdtons into free electrons and holes, and to guarantee fast charge carrier transport from any place in the active layer to the electrodes. The most successfid technique that provides local 3D morpholo information with nanometer resolution in all three dimensions is electron tomography (ET), also referred to as transmission electron microtomography and 3D TEM [27-32]. 

In a first attempt to visualize the 3D organization of the system MDMO-PPV/PCBM having the optimum of 80 wt% of PCBM for highest performance of the device, we were able to obtain detailed 3D information about PCBM-rich domain sizes as well as connectivity of the PCBM domain network within the active 

1112 nm X 1090 nm x 75 nm the dark polymer strands are made here thinner than they are in reality to facilitate visualization) (c) zoom-in of the same volume (with volume dimensions of 227 nm x 227 nm x 75 nm and the thickness of the polymer strands to scale). (Reprinted with permission from Ref [34]. Copyright 2010, Wiley-VCH Verlag GmbH.) 

In an attempt to reveal the three-dimensional organization in the photoactive layer of P3HT/PCBM PSCs, recently its volume morphology was analyzed in detail hy means of ET and the critical morphology parameters contributing to the 

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Volume Characterization of the Photoactive Layer Electron TomographY I 51... 

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