Investigating the morphology of bulk heterojunctions by laser photoemission electron microscopy

The nanoscale morphology of bulk heterojunctions is highly important for the charge dissociation and transport in organic solar cells and ultimately defines the performance of the cell. The visualization of this nanomorphology in terms of domain size and polymer orientation in a fast and straightforward way is therefore of great interest to evaluate the suitability of a film for efficient solar cells. Here, we demonstrate that the morphology of different blends of poly(3-hexylthiophene-2,5-diyl) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) can be imaged and analyzed by employing photoemission electron microscopy.

Automated summary

The nanoscale morphology of bulk heterojunctions plays a crucial role in charge dissociation and transport, affecting the performance of organic solar cells. Photoemission electron microscopy offers a fast and intuitive method to visualize and analyze the nanomorphology of different polymer blends, providing valuable insights for evaluating film suitability.