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 cm2V−1s−1are 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 ≈10−3cm2V−1s−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{[
The rational creation of two-component conjugated polymer systems with high levels of phase purity in each component is challenging but crucial for realizing printed soft-matter electronics. Here, we report a mixed-flow microfluidic printing (MFMP) approach for two-component
- NSF-PAR ID:
- 10170121
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 30
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 17551-17557
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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