Controlling aggregation of diketopyrrolopyrroles in water

Abstract

Charge repulsion can be used to control and fine tune the supramolecular aggregation of amino acid substituted diketopyrrolopyrroles in water. This is a simple method to access a number of different aggregation states with distinct photophysical properties without the need for extensive synthetic tuning, process engineering, or solvent optimisation. Most importantly, these different aggregates show different optical gaps, HOMO-LUMO gaps, electroactivity, and exciton binding energies. These systems expand the absorbance range achieved from one chromophore unit and also create systems with large Stokes shifts. This work therefore answers the demand for tailoring aggregate structures by manipulating charge repulsion in an aqueous environment.