Photoswitching and Thermoresponsive Properties of Conjugated Multi‐chromophore Nanostructured Materials

Conjugated multi‐chromophore organic nanostructured materials have recently emerged as a new class of functional materials for developing efficient light‐harvesting, photosensitization, photocatalysis, and sensor devices because of their unique photophysical and photochemical properties. Here, we demonstrate the formation of various nanostructures (fibers and flakes) related to the molecular arrangement (H‐aggregation) of quaterthiophene (QTH) molecules and their influence on the photophysical properties. XRD studies confirm that the fiber structure consists of >95% crystalline material, whereas the flake structure is almost completely amorphous and the microstrain in flake‐shaped QTH is significantly higher than that of QTH in solution. The influence of the aggregation of the QTH molecules on their photoswitching and thermoresponsive photoluminescence properties is revealed. Time‐resolved anisotropic studies further unveil the relaxation dynamics and restricted chromophore properties of the self‐assembled nano/microstructured morphologies. Further investigations should pave the way for the future development of organic electronics, photovoltaics, and light‐harvesting systems based on π‐conjugated multi‐chromophore organic nanostructured materials.