Conjugated Polymer Mesocrystals with Structural and Optoelectronic Coherence and Anisotropy in Three Dimensions
Journal article, 2022

Semiconducting mesocrystalline bulk polymer specimens that exhibit near-intrinsic properties using channel-die pressing are demonstrated. A predominant edge-on orientation is obtained for poly(3-hexylthiophene-2,5-diyl) (P3HT) throughout 2 mm-thick/wide samples. This persistent mesocrystalline arrangement at macroscopic scales allows reliable evaluation of the electronic charge-transport anisotropy along all three crystallographic axes, with high mobilities found along the π-stacking. Indeed, charge-carrier mobilities of up to 2.3 cm2 V−1 s−1 are measured along the π-stack, which are some of the highest mobilities reported for polymers at low charge-carrier densities (drop-cast films display mobilities of maximum ≈10−3 cm2 V−1 s−1). The structural coherence also leads to an unusually well-defined photoluminescence line-shape characteristic of an H-aggregate (measured from the surface perpendicular to the materials flow), rather than the typical HJ-aggregate feature usually found for P3HT. The approach is widely applicable: to electrical conductors and materials used in n-type devices, such as poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} (N2200) where the mesocrystalline structure leads to high electron transport along the polymer backbones (≈1.3 cm2 V−1 s−1). This versatility and the broad applicability of channel-die pressing signifies its promise as a straightforward, readily scalable method to fabricate bulk semiconducting polymer structures at macroscopic scales with properties typically accessible only by the tedious growth of single crystals.

structural 3D coherence

bulk charge transport

conjugated polymers

mesocrystalline materials

Author

Liyang Yu

Sichuan University

Egon Pavlica

University of Nova Gorica

Ruipeng Li

Brookhaven National Laboratory

Yufei Zhong

Zhejiang University

Carlos Silva

Georgia Institute of Technology

Gvido Bratina

University of Nova Gorica

Christian Müller

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Christian Müller Group

A. Amassian

North Carolina State University

N. Stingelin

Georgia Institute of Technology

Advanced Materials

09359648 (ISSN) 15214095 (eISSN)

Vol. 34 1 2103002

Subject Categories

Textile, Rubber and Polymeric Materials

Materials Chemistry

Condensed Matter Physics

DOI

10.1002/adma.202103002

PubMed

34676923

More information

Latest update

4/5/2022 6