Improving the Robustness of Organic Semiconductors through Hydrogen Bonding

Molecular
organization plays an essential role in organic semiconductors
since it determines the extent of intermolecular interactions that
govern the charge transport present in all electronic applications.
The benefits of hydrogen bond-directed self-assembly on charge transport
properties are demonstrated by comparing two analogous pyrrole-based,
fused heptacyclic molecules. The rationally designed synthesis of
these materials allows for inducing or preventing hydrogen bonding.
Strategically located hydrogen bond donor and acceptor sites control
the solid-state arrangement, favoring the supramolecular expansion
of the π-conjugated surface and the subsequent π-stacking
as proved by X-ray diffraction and computational calculations. The
consistency observed for the performance of organic field-effect transistors
and the morphology of the organic thin films corroborate that higher
stability and thermal robustness are achieved in the hydrogen-bonded
material.