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Abstract 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{[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 cm2V−1s−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.
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Repurposing DNA-binding agents as H-bonded organic semiconductors
Abstract Organic semiconductors are usually polycyclic aromatic hydrocarbons and their analogs containing heteroatom substitution. Bioinspired materials chemistry of organic electronics promises new charge transport mechanism and specific molecular recognition with biomolecules. We discover organic semiconductors from deoxyribonucleic acid topoisomerase inhibitors, featuring conjugated backbone decorated with hydrogen-bonding moieties distinct from common organic semiconductors. Using ellipticine as a model compound, we find that hydrogen bonds not only guide polymorph assembly, but are also critical to forming efficient charge transport pathways along π−conjugated planes when at a low dihedral angle by shortening the end-to-end distance of adjacent π planes. In the π−π stacking and hydrogen-bonding directions, the intrinsic, short-range hole mobilities reach as high as 6.5 cm2V−1s−1and 4.2 cm2V−1s−1measured by microwave conductivity, and the long-range apparent hole mobilities are up to 1.3 × 10–3cm2V−1s−1and 0.4 × 10–3cm2V−1s−1measured in field-effect transistors. We further demonstrate printed transistor devices and chemical sensors as potential applications.
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- Award ID(s):
- 1720633
- PAR ID:
- 10153955
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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