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Although high-temperature operation (i.e., beyond 150°C) is of great interest for many electronics applications, achieving stable carrier mobilities for organic semiconductors at elevated temperatures is fundamentally challenging. We report a general strategy to make thermally stable high-temperature semiconducting polymer blends, composed of interpenetrating semicrystalline conjugated polymers and high glass-transition temperature insulating matrices. When properly engineered, such polymer blends display a temperature-insensitive charge transport behavior with hole mobility exceeding 2.0 cm2/V·s across a wide temperature range from room temperature up to 220°C in thin-film transistors.
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High-density polyethylene—an inert additive with stabilizing effects on organic field-effect transistors
Organic electronics technologies have attracted considerable interest over the last few decades and have become promising alternatives to conventional, inorganic platforms for specific applications. To fully exploit the touted potential of plastic electronics, however, other prerequisites than only electronic functions need to be fulfiled, including good mechanical stability, ease of processing and high device reliability. A possible method to overcome these issues is the employment of insulating:semiconducting polymer blends, which have been demonstrated to display favourable rheological and mechanical properties, generally provided by the insulating component, without negatively affecting the optoelectronic performance of the semiconductor. Here, we demonstrate that binary blends comprising the semicrystalline high-density polyethylene (HDPE) in combination with hole- and electron-transporting organic semiconductors allow fabrication of p-type and n-type thin-film transistors of notably improved device stability and, in some scenarios, improved device performance. We observe, for example, considerably lower subthreshold slopes and drastically reduced bias-stress effects in devices fabricated with a hole-transporting diketopyrrolopyrrole polymer derivative when blended with HDPE and significantly enhanced charge-carrier mobilities and shelf life in case of transistors made with blends between HDPE and the electron-transporting poly{[ N , N ′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)2,6-diyl]- alt -5,5′-(2,2′-bithiophene)}, i.e. P(NDI2OD-T2), also known as N2200, compared to the neat material, highlighting the broad, versatile benefits blending semiconducting species with a semicrystalline commodity polymer can have.
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- Award ID(s):
- 1729737
- PAR ID:
- 10296340
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 8
- Issue:
- 43
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 15406 to 15415
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D0TC03173A
