The Nanoscale Morphology of a PCDTBT:PCBM Photovoltaic Blend

Abstract

Neutron reflectivity and X-ray scattering have been used to characterise the structure of photovoltaic optimised PCDTBT:PCBM (1:4) blend films. A negative gradient of the PCBM forms spontaneously upon film casting – a fortuitous structure that is well matched for efficient charge extraction. Mild thermal annealing at 70 °C does not significantly modify the film structure, and any improvement in device efficiency is likely to be through the removal of trapped casting solvent. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.