Tetraphenylethene-Based Star Shaped Porphyrins: Synthesis, Self-assembly, and Optical and Photophysical Study

Supramolecular
self-assembly and self-organization are simple and
convenient ways to design and create controlled assemblies with organic
molecules, and they have provoked great interest due to their potential
applications in various fields, such as electronics, photonics, and
light-energy conversion. Herein, we describe the synthesis of two
π-conjugated porphyrin molecules bearing tetraphenylethene moieties
with high fluorescence quantum yield. Photophysical and electrochemical
studies were conducted to understand the physical and redox properties
of these new materials, respectively. Furthermore, these derivatives
were used to investigate self-assembly via the solvophobic effect.
The self-assembled aggregation was performed in nonpolar and polar
organic solvents and forms nanospheres and ring-like nanostructures,
respectively. The solution based aggregation was studied by means
of UV–vis absorption, emission, XRD, and DLS analyses. Self-assembled
ring-shape structures were visualized by SEM and TEM imaging. This
ring-shape morphology of nanosized macromolecules might be a good
candidate for the creation of artificial light-harvesting nanodevices.