Perylene-diimide-based n-type semiconductors with enhanced air and temperature stable photoconductor and transistor properties
Graphical abstract
Introduction
Solution-processible organic semiconductors offer potentially inexpensive active components in large area electronics as complementary circuits (CMOS), field effect transistors (FETs), radio-frequency ID tags, sensors, organic light-emitting diodes (OLEDs), and photovoltaics (OPVs) [1]. Remarkable progress has been achieved for hole-transporting (p-type) polymer semiconductors with mobilities exceeding 35 cm2 V−1s−1 and with good air and thermal stability [[2], [3], [4]] – suitable for the above mentioned applications. In contrast, the development of stable, purely electron transporting (n-type) materials with good transport properties, and even more importantly, good air and thermal stability [5,6] remains a critical need in the field, as stable, high performance n-type semiconductors are essential for the development of organic CMOS integrated circuits and the expansion of electron accepting materials for organic photovoltaics. With current n-type conjugated materials, the formation of free electrons along the conjugated bond results in the geometric distortion of the bond and the formation of an unstable radical charge [7]. Hence, they are typically energetically unfavorable. Fortunately, n-type charge formation can be stabilized via conjugated donor-acceptor interactions, and strong n-type transport behavior has been reported for donor-acceptor type conjugated organic semiconductors [8,9]. However, these donor-acceptor conjugated semiconductors typically have commensurate p-type transport with varying degrees of strength. For many applications, the simultaneous presence of p-type transport may constitute a problem. For FETs, the presence of p-type transport in an n-type transistor will lead to a lack of, or limited range of, an OFF state. For OPVs, p-type transport states in the n-type region of an organic solar cell will serve as hole-traps and exciton-recombination sites, reducing the photo-performance of the device.
Perylene-diimides (PDIs) are highly electron-deficient conjugated structures that can exist stably in ambient environments, enabling their application as dyes [10,11]. This electron-deficiency, together with strong intermolecular π- π coupling, results in good n-type transport in well-ordered films of suitably deposited variants of PDI molecules, thereby allowing for numerous electronic applications [[12], [13], [14], [15]]. PDI-based pendant polymers have been synthesized via “click” [16,17] and nitroxide radical mediated routes [18], and these polymers have exhibited good electron mobility in organic field effect transistors [19]. In particular, PDIs are attractive candidates for n-type active materials for organic solar cells [20]; furthermore, the design space for PDI-based organic electronics has expanded via advances in both molecular and device architectures [[21], [22], [23], [24], [25]]. In this paper, we report on the photoconductive properties of a monomer and a pendant polymer, both consisting of PDI with an acrylate-based swallow-tail side-group [26,27]. Devices that we fabricated under ambient conditions showed good transistor and photoconductor performance in air. More significantly, transport properties improved with annealing up to 200 °C in air. The results indicate good environmental stability for these types of PDI organic semiconductors and bodes well for a variety of applications.
Section snippets
Materials
All starting materials and solvents were obtained from Sigma-Aldrich (St. Louis, MO, USA) and were used as received. The synthesis of the PDI monomer and PDI polymer is described herein:
Synthesis of perylene-diimide monomer and pendant polymer
Synthesis of the PDI monomer and PDI polymer is illustrated in Scheme 1. The synthesis of the starting unsymmetric perylene mono-imide mono-anhydride molecule (1) was modified from previous report by Mery et al. [27] The synthesis of the PDI monomer and pendant polymer was modified from previous reports by Haberkorn et al. and Kota et al. [32,33] Starting molecule yields were good (≈90%) for compounds 1 and 2, while moderate yields 50% for hydrolysis into monomer (3) and 60% yield for
Conclusion
In conclusion, we have synthesized two PDI-based materials–a monomer and a pendant polymer. Both materials are solution-processible, have n-type transistor properties and are stable up to 200 °C in air (with additional TGA and DSC data available in ESI). We show through a series of analyses—UV-Vis, electrochemical, photoconductivity and transistor measurements on solution processed films of both materials—that the transport properties of the PDI polymer are better than those of the monomer. We
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgements
This work was funded by the Naval Research Laboratory (NRL) and Office of Naval Research (ONR) 6.1 work unit MA041–06–41–9899 and the Advanced Self-Powered Systems of Integrated Sensors and Technologies (ASSIST), a Nano-Systems Engineering Research Center funded by the National Science Foundation (EEC1160483). All high resolution mass spectrometry measurements were made in the Molecular Education, Technology, and Research Innovation Center (METRIC) at NC State University. The UV–Vis and PL
References (49)
- et al.
Disubstituted perylene diimides in organic field-effect transistors: effect of the alkyl side chains and thermal annealing on the device performance
Org Electron
(2018) - et al.
Separating the impact of oxygen and water on the long-term stability of n-channel perylene diimide thin-film transistors
Org Electron
(2015) - et al.
Perylene diimides based materials for organic solar cells
Dyes Pigments
(2013) - et al.
Perylene diimide based isomeric conjugated polymers as efficient electron acceptors for all-polymer solar cells
Chin J Polym Sci
(2019) - et al.
All-polymer solar cells based on photostable bis(perylene diimide) acceptor polymers
Sol Energy Mater Sol Cells
(2019) - et al.
Theoretical insights into the charge transport in perylene diimides based n-type organic semiconductors
Org Electron
(2012) - et al.
Mobility of electrons and holes in a liquid crystalline perylene diimide thin film with time of flight technique
Chem Phys Lett
(2004) - et al.
Symmetrical and unsymmetrical perylene diimides: their synthesis, photophysical and electrochemical properties
Dyes Pigments
(2006) - et al.
Suppressed charge recombination in polymer solar cells based on perylene diimide derivative acceptors via solvent vapor annealing
Org Electron
(2015) - et al.
Effect of annealing on bulk heterojunction organic solar cells based on copper phthalocyanine and perylene derivative
Synth Met
(2012)
High thermal stability solution-processable narrow-band gap molecular semiconductors
J Am Chem Soc
General strategy for self-assembly of highly oriented nanocrystalline semiconducting polymers with high mobility
Nano Lett
High-mobility air-stable naphthalene diimide-based copolymer containing extended pi-conjugation for n-channel organic field effect transistors
Adv Funct Mater
Importance of unpaired electrons in organic electronics
J Polym Sci, Polym Chem Ed
25th anniversary article: recent advances in n-type and ambipolar organic field-effect transistors
Adv Mater
Development of n-type organic semiconductors for thin film transistors: a viewpoint of molecular design
J Mater Chem C
High performance pigments
Spectral tuning of organic nanocolloids by controlled molecular interactions
ACS Nano
Organic n-channel transistors based on core-cyanated perylene carboxylic diimide derivatives
J Am Chem Soc
Rylene and related diimides for organic electronics
Adv Mater
Non-fullerene small molecule acceptors based on perylene diimides
J Mater Chem A
Simply complex: the efficient synthesis of an intricate molecular acceptor for high-performance air-processed and air-tested fullerene-free organic solar cells
Chem Mater
Modular synthesis of poly(perylene bisimides) using click chemistry: a comparative study
Polym Chem-Uk
Cited by (16)
Functionalized polysiloxanes with perylene diimides and poly(ethylene glycol): Synthesis and properties
2022, European Polymer JournalCitation Excerpt :Perylene-3,4:9,10-tetracarboxylic acid diimide (PDI) derivatives, a part of the rylene family, are one of the most important groups of organic dyes and pigments [1,2]. Their applications include industrial paints [3], organic solar cells [4], organic field effect transistors [5], fluorescence markers [6], photosensitizers [7,8], and energy storage [9]. PDI’s varied applications stems from its intense absorption of visible light, high chemical stability, good electrical conductivity, and high fluorescence efficiency [10,11].
Fast visible light-induced synthesis of annulated perylene bisimides
2020, Dyes and PigmentsCitation Excerpt :As first synthesized in 1910s, perylene-3, 4, 9, 10-bisimides (PBIs) have become the most popular derivatives among rylene family [1–6]. Apart from their unique roles as industrial dyes, the exceptional photochemical/physical properties of PBIs, e.g. photo/thermal stabilities, high extinction coefficients, fluorescence quantum yields, long-extended π-structures, unique HOMO-LUMO level for n-type semiconductors, promote themselves as star molecules and important functional building blocks in various academic fields of organic field-effect transistors (OFET) [7–9], organic photovoltaics (OPV) [10–12], thermoelectric materials (TE) [13,14], supramolecular self-assembly [15–17] as well as fluorescent sensors [18–20]. Development of new PBI derivatives mainly includes two means: 1) Amidation from the bisimides and 2) Annulation from the perylene π-conjugation core.
- 1
Authors equally contributed to this work.