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Title: Semi-paracrystallinity in semi-conducting polymers
Precise determination of structural organization of semi-conducting polymers is of paramount importance for the further development of these materials in organic electronic technologies. Yet, prior characterization of some of the best-performing materials for transistor and photovoltaic applications, which are based on polymers with rigid backbones, often resulted in conundrums in which X-ray scattering and microscopy yielded seemingly contradicting results. Here we solve the paradox by introducing a new structural model, i.e. , semi-paracrystalline organization. The model establishes that the microstructure of these materials relies on a dense array of small paracrystalline domains embedded in a more disordered matrix. Thus, the overall structural order relies on two parameters: the novel concept of degree of paracrystallinity ( i.e. , paracrystalline volume/mass fraction, introduced here for the first time) and the lattice distortion parameter of paracrystalline domains ( g -parameter from X-ray scattering). Structural parameters of the model are correlated with long-range charge carrier transport, revealing that charge transport in semi-paracrystalline materials is particularly sensitive to the interconnection of paracrystalline domains.  more » « less
Award ID(s):
1934374
PAR ID:
10415414
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Materials Horizons
Volume:
9
Issue:
4
ISSN:
2051-6347
Page Range / eLocation ID:
1196 to 1206
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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