Amorphous Self-Assembled Molecule with Distorted Backbone Suppresses Aggregation for Highly Efficient Inverted Perovskite Solar Cells

To overcome this limitation, we rationally design a novel SAM, (4-(2,7-bis(4-methoxyphenyl)-9,9-dimethylacridin-10(9H)-yl)butyl)phosphonic acid (MeO-PhAPA), featuring a structurally distorted backbone.

The core structure of MeO-PhAPA integrates an sp³-hybridized carbon atom bonded to two methyl groups, which imposes pronounced molecular distortion that breaks molecular planarity and effectively suppresses deleterious π-π stacking. Additionally, the single-bond-linked two methoxyphenyl substituents further increase steric hindrance. This tailored molecular design robustly suppresses intermolecular aggregation of MeO-PhAPA, favoring the formation of a uniform, well-wetted amorphous thin film.