On the unipolarity of charge transport in methanofullerene diodes
Source abstract
Abstract
Abstract Fullerenes are electron transporting organic semiconductors with a wide range of applications. In particular, methanofullerenes have been the preferred choice for solution-processed solar cells and photodiodes. The wide applicability of fullerenes as both ‘n-type’ transport materials and electron acceptors is clear. However, what is still a matter of debate is whether the fullerenes can also support efficient transport of holes, particularly in diode geometries. In this letter, we utilize a number of recently developed experimental methods for selective electron and hole mobility measurements. We show for the two most widely used solution processable fullerenes, PC70- and-PC60BM, that whilst both exhibit electron mobilities as high as 10−3 cm2/Vs, their hole mobilities are < 10−9 cm2/Vs. Thus charge transport in these fullerenes can be considered predominantly unipolar in diode configurations.
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Research context
OpenAlex topics: Organic Electronics and Photovoltaics · Fullerene Chemistry and Applications · Molecular Junctions and Nanostructures
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References (29)
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