EAGER: Superlattice-induced polycrystalline and single-crystalline structures in conjugated polymers

Stanford University, Stanford CA

Investigators

Abstract

NON-TECHNICAL: Polymer semiconductors are promising for flexible electronics. However, their charge carrier mobilities are limited by the highly disordered thin film morphology and trap-dominated charge transport. Thus, it remains a grand challenge to reduce the disorder and realize the full potential of conjugated polymers for charge transport. The goal of this project is to explore a method for epitaxial growth of polymer semiconductor single crystals with two-dimensional metal halide perovskite (MHP) single crystals as interacting substrates. If successful, it will allow direct measurement of intrinsic intra- and interchain charge transport in polymer semiconductors. With less defects as traps, it may be possible to observe unprecedented charge transport. This work will provide fundamental insights on conjugated polymer heteroepitaxial crystal growth. The techniques investigated here may be further developed in the future for larger-scale assembly and for systematic investigation of the structure-property relationship for charge transport in polymer semiconductors. Breaking the disorder-dominated charge transport limit of conjugated polymers may potentially bring the field to a new level and opens new applications previously not possible for various optoelectronic and sensing applications. The materials investigated here can be readily integrated into teaching, education, and outreach. TECHNICAL: Polymer semiconductors are promising for flexible electronics. However, their charge carrier mobilities are limited by the highly disordered thin film morphology and trap-dominated charge transport. Thus, it remains a grand challenge to reduce the disorder and realize the full potential of conjugated polymers for charge transport. The goal of this project is to explore a method for epitaxial growth of polymer semiconductor single crystals with two-dimensional metal halide perovskite (MHP) single crystals as interacting substrates. If successful, it will allow direct measurement of intrinsic intra- and interchain charge transport in polymer semiconductors. With less defects as traps, it may be possible to observe unprecedented charge transport. Polymer semiconductors will be prepared to systematically investigate structure property relationships for single crystalline structure formation and charge transport. Various types of two-dimensional perovskite single crystals will be used as templates to guide the assembly of organic semiconducting oligomers and polymers. This work will provide fundamental insights on conjugated polymer heteroepitaxial crystal growth. The techniques investigated here may be further developed in the future for larger-scale assembly and for systematic investigation of the structure-property relationship for charge transport in polymer semiconductors. Breaking the disorder-dominated charge transport limit of conjugated polymers may potentially bring the field to a new level and opens new applications previously not possible for various optoelectronic and sensing applications. The materials investigated here can be readily integrated into teaching, education, and outreach. . This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.