Polymer-Assisted Single Crystal Engineering of Organic Semiconductors To Alter Electron Transport

A new
crystal phase of a naphthalenediimide derivative (α-DPNDI) has
been prepared via a facial polymer-assisted method. The stacking pattern
of DPNDI can be tailored from the known one-dimensional (1D) ribbon
(β phase) to a novel two-dimensional (2D) plate (α phase)
through the assistance from polymers. We believe that the presence
of polymers during crystal growth is likely to weaken the direct π–π
interactions and favor side-to-side C–H−π contacts.
Furthermore, β phase architecture shows electron mobility higher
than that of the α phase in the single-crystal-based OFET. Theoretical
calculations not only confirm that β-DPNDI has an electron transport
performance better than that of the α phase but also indicate
that the α phase crystal displays 2D transport while the β
phase possesses 1D transport. Our results clearly suggest that polymer-assisted
crystal engineering should be a promising approach to alter the electronic
properties of organic semiconductors.