Subphthalocyanine-triangulene dyads: Property tuning for light-harvesting device applications

Organic photovoltaics relies on the development of stable chromophores and redox-active organic molecules with tailor-made HOMO/LUMO energies. Here, we present the synthesis and properties of novel dyads composed of boron subphthalocyanine (SubPc) and triangulene units, connected either at the peripheral position of the subphthalocyanine or at the axial boron. The connectivity has strong implications for the absorption and fluorescence properties of the dyads, as well as their redox properties. While the SubPc unit has a bowl shape, triangulene is a planar structural unit that allows dyads to dimerize in the solid state on account of pi-stacking interactions as shown by X-ray crystallography of one of the dyads. The electronic properties were also studied computationally by density functional theory methods. Excellent agreement between experimental and computed data were obtained, showing that our computational method is a strong tool in the rational design of optimum molecules to ultimately obtain finely tuned molecules for device applications.

Automated summary

This study presents the synthesis and properties of novel dyads composed of boron subphthalocyanine (SubPc) and triangulene units. The dyads are able to dimerize in the solid state through pi-stacking interactions, as confirmed by X-ray crystallography. Computational methods were used to study the electronic properties, and the results were in excellent agreement with experimental data.