Three-Bladed Rylene Propellers with Three-Dimensional Network Assembly for Organic Electronics

Two kinds of conjugated C3-symmetric
perylene dyes, namely, triperylene hexaimides (TPH) and selenium-annulated
triperylene hexaimides (TPH-Se), are efficiently synthesized. Both
TPH and TPH-Se have broad and strong absorption in the region 300–600
nm together with suitable LUMO levels of about −3.8 eV. Single-crystal
X-ray diffraction studies show that TPH displays an extremely twisted
three-bladed propeller configuration and a unique 3D network assembly
in which three PBI subunits in one TPH molecule have strong π–π
intermolecular interactions with PBI subunits in neighboring molecules.
The integration of selenophene to TPH endows TPH-Se with a more distorted
propeller configuration and a more compact 3D network assembly due
to the Se···O interactions. A single-crystal transistor
confirms that both TPH and TPH-Se possess good electron-transport
ability. TPH and TPH-Se acceptor-based solar cells show high power
conversion efficiency of 8.28% and 9.28%, respectively, which mainly
results from the combined properties of broad and strong absorption
ability, appropriate LUMO level, desirable aggregation, high electron
mobility, and good film morphology with the polymer donor.