Imagine that a molecule or a macromolecule needs to be assembled into a structure or morphology that is rare or not preferred by the molecule. How can the molecule be directed to assemble the way we need it? Finding the answer to this question will have solved a very important problem in organic photovoltiac cells. Plus it will make a major impact in the prediction of condensed phase structures.

For efficient organic or hybrid photovoltaic cells, hole-conducting (blue in the figure) and electron-conducting (orange in the figure) organic moieties need to be assembled into segregated structures. This allows the exciton to split at the interface. Yet, it is favorable for hole-conducting moieties mix with electron-conducting moieties. How do we keep them separated?

Our approach involves appending groups to electron-rich and electron-poor moieties such that the interaction between these groups will be unfavorable. The underlying hypothesis of our approach is that mixing of electron-rich and electron-poor moieties will be disfavored because of the immisciblity between the groups appended on them.

Impact of our Work: Fundamental understanding of how competing interactions direct condensed phase structures, and Segregated morphologies for efficient organic photovoltaic cells.