Impact of polymorphism on the optoelectronic properties of a low-bandgap semiconducting polymer.

ABSTRACT: Polymorphism of organic semiconducting materials exerts critical effects on their physical properties such as optical absorption, emission and electrical conductivity, and provides an excellent platform for investigating structure-property relations. It is, however, challenging to efficiently tune the polymorphism of conjugated polymers in aggregated, semi-crystalline phases due to their conformational freedom and anisotropic nature. Here, two distinctly different semi-crystalline polymorphs (?1 and ?2) of a low-bandgap diketopyrrolopyrrole polymer are formed through controlling the solvent quality, as evidenced by spectroscopic, structural, thermal and charge transport studies. Compared to ?1, the ?2 polymorph exhibits a lower optical band gap, an enhanced photoluminescence, a reduced ?-stacking distance, a higher hole mobility in field-effect transistors and improved photocurrent generation in polymer solar cells. The ?1 and ?2 polymorphs provide insights into the control of polymer self-organization for plastic electronics and hold potential for developing programmable ink formulations for next-generation electronic devices.

SUBMITTER: Li M 

PROVIDER: S-EPMC6599012 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature