FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W3035670900> ?p ?o ?g. }

• W3035670900 endingPage "1326" @default.
• W3035670900 startingPage "1310" @default.
• W3035670900 abstract "Challenges and opportunities:•Designing and synthesizing novel highly electron-deficient building blocks with very low-lying and delocalized lowest unoccupied molecular orbitals (LUMOs), reduced steric hindrance, and excellent solubilizing capability.•Developing facile polymerization methods that can effectively incorporate various electron-deficient building blocks into polymers. The n-type polymers have good solubility, a high content of acceptor units in polymeric backbones, optimized optoelectronic properties, high molecular weight, and minimal structural defects.•Achieving excellent n-type performance with robust stability in material processing and under device operation conditions. High-performance n-type (electron-transporting or n-channel) polymer semiconductors are critical components for the realization of various organic optoelectronic devices and complementary circuits, and recent progress has greatly advanced the performance of organic thin-film transistors, all-polymer solar cells, and organic thermoelectrics, to cite just a few. This Perspective focuses on the recent development of high-performance n-type polymer structures, particularly those based on the most investigated and novel electron-deficient building blocks, as well as summarizes the performance achieved in the above devices. In addition, this Perspective offers our insights into developing new electron-accepting building blocks and polymer design strategies, as well as discusses the challenges and opportunities in advancing n-type device performance. High-performance n-type (electron-transporting or n-channel) polymer semiconductors are critical components for the realization of various organic optoelectronic devices and complementary circuits, and recent progress has greatly advanced the performance of organic thin-film transistors, all-polymer solar cells, and organic thermoelectrics, to cite just a few. This Perspective focuses on the recent development of high-performance n-type polymer structures, particularly those based on the most investigated and novel electron-deficient building blocks, as well as summarizes the performance achieved in the above devices. In addition, this Perspective offers our insights into developing new electron-accepting building blocks and polymer design strategies, as well as discusses the challenges and opportunities in advancing n-type device performance. n-Type (electron-transporting or n-channel) organic semiconductors are essential for several organic optoelectronic devices given that p-n junction, complementary metal-oxide-semiconductor-like circuitry, and electron-transporting interlayer are ubiquitous in these devices.1Usta H. Facchetti A. Marks T.J. n-Channel semiconductor materials design for organic complementary circuits.Acc. Chem. Res. 2011; 44: 501-510Crossref PubMed Scopus (551) Google Scholar,2Yang J. Zhao Z. Wang S. Guo Y. Liu Y. Insight into high-performance conjugated polymers for organic field-effect transistors.Chem. 2018; 4: 1-2Abstract Full Text Full Text PDF Scopus (106) Google Scholar To this end, a vast number of n-type organic semiconductors have been invented, including those based on both small molecules and polymers, each of which have their own pros and cons. Compared with small molecules, polymers can afford formulations with enhanced film-forming properties, films with improved morphological robustness, and films and devices with superior mechanical flexibility and stretchability.3Zhao D. Chen J. Wang B. Wang G. Chen Z. Yu J. Guo X. Huang W. Marks T.J. Facchetti A. Engineering intrinsic flexibility in polycrystalline molecular semiconductor films by grain boundary plasticization.J. Am. Chem. Soc. 2020; 142: 5487-5492Crossref PubMed Scopus (10) Google Scholar,4Fan Q. Su W. Chen S. Kim W. Chen X. Lee B. Liu T. Méndez-Romero U.A. Ma R. Yang T. et al.Mechanically robust all-polymer solar cells from narrow band gap acceptors with hetero-bridging atoms.Joule. 2020; 4: 658-672Abstract Full Text Full Text PDF Scopus (101) Google Scholar Polymers are more amenable to solution-based processing techniques because of the broader rheological properties of the corresponding solutions and hence can enable high-throughput cost-effective device fabrication over large areas. These features can power the development of new electronic products, such as flexible and stretchable displays, wearable electronics, and disposable sensors.5Yu X. Xie Z. Yu Y. Lee J. Vazquez-Guardado A. Luan H. Ruban J. Ning X. Akhtar A. Li D. et al.Skin-integrated wireless haptic interfaces for virtual and augmented reality.Nature. 2019; 575: 473-479Crossref PubMed Scopus (142) Google Scholar Therefore, developing high-performance n-type polymers plays a paramount role in advancing the organic electronics field. To realize efficient electron transport in polymer semiconductors, and thus n-type behavior in the corresponding devices, the lowest unoccupied molecular orbital (LUMO) energy levels of the semiconductor should be sufficiently low for efficient electron injection (or generation), extraction, and stable charge transport. To fulfill this requirement, polymer backbones have been typically functionalized with strong electron-withdrawing groups (EWGs), such as carbonyl (C=O), fluorine (F) or fluorocarbon (CnF2n+1), and cyano (CN) groups, which typically impose sizable steric demand on the (hetero)arene backbone and negatively affect polymer chain planarity.6Bronstein H. Nielsen C.B. Schroeder B.C. McCulloch I. The role of chemical design in the performance of organic semiconductors.Nat. Rev. Chem. 2020; 4: 66-77Crossref Scopus (96) Google Scholar For small molecules, these EWGs can be installed on both terminal rings to minimize steric hindrance and optimize the electronic structure, as exemplified by the groundbreaking small molecular fluorocarbon-functionalized oligothiophenes and arenes in thin-film transistors (TFTs)1Usta H. Facchetti A. Marks T.J. n-Channel semiconductor materials design for organic complementary circuits.Acc. Chem. Res. 2011; 44: 501-510Crossref PubMed Scopus (551) Google Scholar and acceptors (ITIC and Y6) in non-fullerene organic solar cells (OSCs).7Yan C. Barlow S. Wang Z. Yan H. Jen A.K.-Y. Marder S.R. Zhan X. Non-fullerene acceptors for organic solar cells.Nat. Rev. Mater. 2018; 3: 18003Crossref Scopus (1249) Google Scholar,8Yuan J. Zhang Y.Q. Zhou L.Y. Zhang G.C. Yip H.L. Lau T.K. Lu X.H. Zhu C. Peng H.J. Johnson P.A. et al.Single-junction organic solar cell with over 15% efficiency using fused-ring acceptor with electron-deficient core.Joule. 2019; 3: 1140-1151Abstract Full Text Full Text PDF Scopus (1773) Google Scholar However, such a design is not feasible for polymers. The sizable steric hindrance and the lack of solubilizing power in some strong EWGs, such as fluorocarbon and CN groups, are the two major factors limiting n-type polymers and their device performance. To address these challenges, n-type polymer design consists of functionalizing fused (hetero)arenes with strong EWGs in a favorable fashion to yield highly electron-deficient building blocks, which are then typically combined with conventional (hetero)arene and/or π-bridge blocks to afford π-conjugated polymers with proper electronic structures, backbone conformation, and film morphologies, enabling high-performance organic thin-film transistors (OTFTs), all-polymer solar cells (all-PSCs), and organic thermoelectrics (OTEs). Thus, the key to developing n-type polymers is the invention of highly electron-deficient (hetero)arene building blocks with excellent solubilizing capability, favorable geometry, and optimized electronic structure. In this Perspective, we summarize the most prominent and recently developed electron-transporting polymers and their n-type performance in various devices based on the key EWG unit used for the design of the key electron-deficient building block, specifically imide, amide, B←N unit, and CN groups (Figure 1). We also offer insights into the challenges and opportunities for their design and synthetic strategies. Note that in addition to the above four categories, some other structurally novel electron-deficient building blocks, e.g., thienoquinoid,9Kawabata K. Saito M. Osaka I. Takimiya K. Very small bandgap π-conjugated polymers with extended thienoquinoids.J. Am. Chem. Soc. 2016; 138: 7725-7732Crossref PubMed Scopus (69) Google Scholar,10Osaka I. Abe T. Mori H. Saito M. Takemura N. Koganezawa T. Takimiya K. Small band gap polymers incorporating a strong acceptor, thieno[3,2-B]thiophene-2,5-dione, with P-channel and ambipolar charge transport characteristics.J. Mater. Chem. C. 2014; 2: 2307-2312Crossref Google Scholar thiadiazolobenzotriazole,11Wang Y. Hasegawa T. Matsumoto H. Mori T. Michinobu T. Rational design of high-mobility semicrystalline conjugated polymers with tunable charge polarity: beyond benzobisthiadiazole-based polymers.Adv. Funct. Mater. 2017; 27: 1604608Crossref Scopus (52) Google Scholar and thiadiazoloquinoxaline12An C. Li M. Marszalek T. Li D. Berger R. Pisula W. Baumgarten M. Thiadizoloquinoxaline-based low-bandgap conjugated polymers as ambipolar semiconductors for organic field effect transistors.Chem. Mater. 2014; 26: 5923-5929Crossref Scopus (34) Google Scholar to cite a few, can also enable n-type transporting polymers. However, because of their relatively weak electron-withdrawing capability, the corresponding polymers show limited n-type performance or considerable ambipolar characteristics. In this section, we briefly describe the basic structure of the devices we discuss in this Perspective (Figure 1C), the definition of key performance parameters, and the elementary equations used for their calculations from the experimental data. An OTFT device is composed of three electrodes (source, drain, and gate), a gate dielectric layer, and an organic semiconductor layer; the left column in Figure 1C shows a representative bottom-gate top-contact OTFT architecture. When a gate potential is applied (VG ≠ 0 V), the device turns on (ISD ≠ 0 A) as a result of charge-carrier accumulation in the semiconductor layer. The OTFT performance parameters are extracted from the output and transfer current-voltage plots. Among them, the most critical is the field-effect mobility (μ), which describes how fast charge carriers drift, and it is calculated (in saturation) by the equation ID=μCiW2L(VGS−VT)2. Second, the bulk-heterojunction (BHJ) OSC consists of a photoactive layer (electron donor + acceptor semiconductor blend) sandwiched between a transparent electrode (typically an anode) and a low-work-function metal electrode (the cathode). Interfacial layers favoring electron and hole extraction, i.e., electron-transporting layers (ETLs) and hole-transporting layers (HTLs), are also used to enhance the process (center column in Figure 1C). Upon light exposure, excitons diffuse to the donor-acceptor interface of the blend, dissociate into holes and electrons (which drift via the separate donor and acceptor domains), and are eventually collected at the anode and cathode electrodes. The light-to-charge power conversion efficiency (PCE) is the most important parameter and is defined by the formula PCE= Voc × Jsc × FF, where Voc is the open-circuit voltage, Jsc is the short circuit current, and FF is the fill factor. Finally, an OTE device operates between two metal plates at distinct temperatures, Thot and Tcold, creating an electrical current via a temperature gradient (right column in Figure 1C). The thermoelectric efficiency can be accessed in terms of the power factor (PF) given by the equation PF= S2 × σ, where S is the Seebeck coefficient (μV K−1) and σ is electrical conductivity (S cm−1). Because typical S values of most p-type and n-type polymers are comparable, σ is an important parameter for evaluating the thermoelectric performance. Note that σ = n × μ, where n is the carrier density and μ is the bulk carrier mobility. The great success of rylene diimides for n-type small-molecule semiconductors triggered their use for designing n-type polymers.13Sun H. Wang L. Wang Y. Guo X. Imide-functionalized polymer semiconductors.Chem. Eur. J. 2019; 25: 87-105Crossref PubMed Scopus (41) Google Scholar Among them, naphthalene diimide (NDI) polymers attracted the most attention because of their facile synthesis, good solubility, and deep-positioned LUMO levels. The major breakthrough in the development of n-type polymers was enabled by the emergence of P(NDI2OD-T2) (also known as N2200; Figure 1B), a NDI- and bithiophene-based co-polymer, which opened a new era of n-type polymer research and drove extensive efforts into NDI polymers.14Yan H. Chen Z.H. Zheng Y. Newman C. Quinn J.R. Dötz F. Kastler M. Facchetti A. A high-mobility electron-transporting polymer for printed transistors.Nature. 2009; 457: 679-686Crossref PubMed Scopus (2407) Google Scholar,15Guo X. Watson M.D. Conjugated polymers from naphthalene bisimide.Org. Lett. 2008; 10: 5333-5336Crossref PubMed Scopus (256) Google Scholar Initial electron mobility (μe) values in OTFTs of this polymer ranged between 0.1 and 0.85 cm2 V–1 s–1 depending on the film processing and device architecture. The performance of NDI polymers in various optoelectronic devices has been steadily improved by optimizing polymer molecular weight, N-alkyl chain engineering, semiconductor film processing, and device engineering.16Lee C. Lee S. Kim G.U. Lee W. Kim B.J. Recent advances, design guidelines, and prospects of all-polymer solar cells.Chem. Rev. 2019; 119: 8028-8086Crossref PubMed Scopus (233) Google Scholar For OTFT applications, achieving considerable solid-state aggregation, polymer-chain alignment, and high film crystallinity is key to obtaining high mobility. For instance, N2200 polymer-chain alignment by natural brush and bar coating has enabled μe values as high as 2.3 cm2 V–1 s–1 and 6.4 cm2 V–1 s–1, respectively.17Bucella S.G. Luzio A. Gann E. Thomsen L. McNeill C.R. Pace G. Perinot A. Chen Z. Facchetti A. Caironi M. Macroscopic and high-throughput printing of aligned nanostructured polymer semiconductors for MHz large-area electronics.Nat. Commun. 2015; 6: 8394Crossref PubMed Scopus (209) Google Scholar,18Wang G. Huang W. Eastham N.D. Fabiano S. Manley E.F. Zeng L. Wang B. Zhang X. Chen Z. Li R. et al.Aggregation control in natural brush-printed conjugated polymer films and implications for enhancing charge transport.Proc. Natl. Acad. Sci. USA. 2017; 114: E10066-E10073Crossref PubMed Scopus (85) Google Scholar Replacing the alkyl side chain of N2200 with a semi-fluoroalkyl one affords polymer PNDIF-T2 (Figure 2) with remarkable crystallinity of both the backbone and side chain, which is induced by the semi-fluoroalkyl chain’s strong self-organization ability.19Kang B. Kim R. Lee S.B. Kwon S.K. Kim Y.H. Cho K. Side-chain-induced rigid backbone organization of polymer semiconductors through semifluoroalkyl side chains.J. Am. Chem. Soc. 2016; 138: 3679-3686Crossref PubMed Scopus (176) Google Scholar As a result, unipolar n-type performance with an excellent μe of 6.50 cm2 V–1 s–1 is realized. Efficient π-orbital overlap between NDI and the adjacent unit is another important factor for improving electron mobility. Replacing the sulfur with selenium, which has a larger atomic radius, yields a biselenophene analog of N2200, PNDIBS (Figure 2), which shows a higher μe in the same device configuration.20Hwang Y.-J. Ren G. Murari N.M. Jenekhe S.A. n-Type naphthalene diimide–biselenophene copolymer for all-polymer bulk heterojunction solar cells.Macromolecules. 2012; 45: 9056-9062Crossref Scopus (111) Google Scholar Taking the advantages of selenium substitution, Liu et al. developed an acceptor-1-donor-acceptor-2-donor (A1-D-A2-D) type polymer, PNBSF, by using a selenophene bridge (Figure 2), which not only reduced the steric hindrance between two acceptor (A) units but also enabled PNBSF with a smoother surface morphology and closer π-π stacking than the thiophene analog. PNBSF delivered a unipolar n-type OTFT performance with a μe of 3.50 cm2 V–1 s–1.21Zhao Z. Yin Z. Chen H. Zheng L. Zhu C. Zhang L. Tan S. Wang H. Guo Y. Tang Q. Liu Y. High-performance, air-stable field-effect transistors based on heteroatom-substituted naphthalenediimide-benzothiadiazole copolymers exhibiting ultrahigh electron mobility up to 8.5 cm V-1 s-1.Adv. Mater. 2017; 29: 1602410Crossref Scopus (141) Google Scholar Interestingly, theoretical and experimental data revealed that there is a significant torsional angle of 30°–40° between NDI and the adjacent thiophene ring in N2200, which suppresses π-orbital delocalization and polymer-chain stacking, thus potentially limiting intrinsic charge transport. To this end, Heeney designed a new NDI monomer featuring two flanking vinyl stannyl groups and synthesized a series of NDI polymers with significantly improved planarity due to reduced steric hindrance and the formation of intramolecular O···H hydrogen bonds. Among them, PNDIV-BT exhibited a champion μe of 0.07 cm2 V–1 s–1 in OTFTs, which remains lower than that of N2200.22Fei Z. Han Y. Martin J. Scholes F.H. Al-Hashimi M. AlQaradawi S.Y. Stingelin N. Anthopoulos T.D. Heeney M. Conjugated copolymers of vinylene flanked naphthalene diimide.Macromolecules. 2016; 49: 6384-6393Crossref Scopus (34) Google Scholar Thus, planarity does not necessary translate to enhanced electron transport in a TFT architecture. On the basis of this strategy, Michinobu recently developed polymer P4 (Figure 2), which incorporated a second well-tailored acceptor (A) unit to yield a polymer with an A1-D-A2-D backbone (Figure 2). P4 also has a planar backbone conformation and a highly crystalline microstructure with a close π-π stacking distance (3.40 Å). As a result, a remarkable μe of 7.16 cm2 V−1 s−1 was attained.23Wang Y. Hasegawa T. Matsumoto H. Michinobu T. Significant improvement of unipolar n-type transistor performances by manipulating the coplanar backbone conformation of electron-deficient polymers via hydrogen bonding.J. Am. Chem. Soc. 2019; 141: 3566-3575Crossref PubMed Scopus (51) Google Scholar In addition to OTFT applications, NDI polymers have attracted substantial interest as alternative acceptors in OSCs.24Zhou N. Facchetti A. Naphthalenediimide (NDI) polymers for all-polymer photovoltaics.Mater. Today. 2018; 21: 377-390Crossref Scopus (89) Google Scholar Benefiting from the synthesis of tailored-made polymer donors along with material processing and device engineering, steady progress has been achieved in N2200-based all-PSCs, which recently showed a record PCE of 11.76% enabled by multi-length scaled film morphology.25Zhu L. Zhong W. Qiu C. Lyu B. Zhou Z. Zhang M. Song J. Xu J. Wang J. Ali J. et al.Aggregation-induced multilength scaled morphology enabling 11.76% efficiency in all-polymer solar cells using printing fabrication.Adv. Mater. 2019; 31: e1902899Crossref PubMed Scopus (119) Google Scholar For all-PSC applications it is necessary to realize (besides an n-type polymer acceptor with high electron mobility) good compatibility and miscibility with the p-type polymer donor to achieve high efficiency. High-mobility NDI polymers are typically very crystalline and exhibit strong aggregation, which can negatively affect the miscibility with the polymer donor, yielding a coarse phase separation in the all-polymer blend film. In this regard, side-chain engineering, heteroatom substitution, molecular-weight optimization, and random terpolymerization are powerful approaches for optimizing the polymer crystallinity and thus tuning the blend morphology.16Lee C. Lee S. Kim G.U. Lee W. Kim B.J. Recent advances, design guidelines, and prospects of all-polymer solar cells.Chem. Rev. 2019; 119: 8028-8086Crossref PubMed Scopus (233) Google Scholar Among them, random terpolymerization is a facile yet effective route to achieving a delicate balance between crystallinity and miscibility without sacrificing charge mobilities.26Lee J. Lee S.M. Chen S. Kumari T. Kang S.H. Cho Y. Yang C. Organic photovoltaics with multiple donor-acceptor pairs.Adv. Mater. 2019; 31: e1804762Crossref PubMed Scopus (50) Google Scholar In a pioneering study, Jenekhe and co-workers27Hwang Y.J. Earmme T. Courtright B.A.E. Eberle F.N. Jenekhe S.A. n-Type semiconducting naphthalene diimide-perylene diimide copolymers: controlling crystallinity, blend morphology, and compatibility toward high-performance all-polymer solar cells.J. Am. Chem. Soc. 2015; 137: 4424-4434Crossref PubMed Scopus (306) Google Scholar designed and synthesized a series of random terpolymers based on the NDI-biselenophene parent co-polymer with bulky perylene diimides (PDI) as the third component, showing suppressed crystallinity versus the parent polymer. As a result of improved compatibility and blend morphology, the PCE of the terpolymer 30PDI (30% PDI moiety; Figure 2) was increased to 6.3% from that (1.23%) of the parent co-polymer. Inspired by this work, many efforts have been devoted to systematically optimizing film crystallinity, light absorption, and frontier molecular orbital (FMO) levels of n-type terpolymers by incorporating various third components. For instance, Huang and co-workers replaced a fraction of the 2-octyldodecyl chain in N2200 with a linear oligoethylene oxide (OE) chain to tune polymer packing, phase separation, and vertical phase gradation. As a result, a high PCE of 8% and a remarkable FF of 0.75 were achieved by the polymer NOE10 with 10% OE chain (Figure 2).28Liu X. Zhang C. Duan C. Li M. Hu Z. Wang J. Liu F. Li N. Brabec C.J. Janssen R.A.J. et al.Morphology optimization via side chain engineering enables all-polymer solar cells with excellent fill factor and stability.J. Am. Chem. Soc. 2018; 140: 8934-8943Crossref PubMed Scopus (140) Google Scholar Bao and co-workers recently demonstrated a terpolymerization strategy by incorporating a bulky 2,6-diisopropyl-phenyl side chain to fine-tune the aggregation and crystallinity of N2200 derivatives, resulting in an optimized BHJ morphology for the PNDI0.5-based (Figure 2) all-PSCs and thus a significantly improved PCE from 5.1% to 8.5%.29Wu Y. Schneider S. Walter C. Chowdhury A.H. Bahrami B. Wu H.C. Qiao Q. Toney M.F. Bao Z. Fine-tuning semiconducting polymer self-aggregation and crystallinity enables optimal morphology and high-performance printed all-polymer solar cells.J. Am. Chem. Soc. 2020; 142: 392-406Crossref PubMed Scopus (54) Google Scholar NDI polymers have also gained significant attention for n-type OTEs because of their high electron affinity and mobility. Facchetti and co-workers reported the dithiazole analog of N2200, P(NDI2OD-Tz2) (Figure 2), synthesized via active-zinc polymerization with the new monomer NDI2OD-Tz2Br. P(NDI2OD-Tz2) showed a reduced chain steric demand and thus exhibited a more planar backbone than N2200, resulting in a more closely packed structure. Additionally, the more electron-deficient thiazole (versus thiophene) increased the electron affinity of P(NDI2OD-Tz2),30Wang S. Sun H. Erdmann T. Wang G. Fazzi D. Lappan U. Puttisong Y. Chen Z. Berggren M. Crispin X. et al.A chemically doped naphthalenediimide-bithiazole polymer for n-type organic thermoelectrics.Adv. Mater. 2018; 30: e1801898Crossref PubMed Scopus (81) Google Scholar which yielded an enhanced electrical conductivity (σ) of ≈ 0.1 S cm−1 compared with that (0.003 S cm−1) of N2200 after doping. In addition to the high mobility, efficient electron doping is another key factor for improving σ, but it is challenging to realize for NDI polymers because of their poor miscibility with n-dopants. To this end, Koster and co-workers developed a new strategy. The alkyl side chain of N2200 was replaced with a polar triethylene-glycol-based one to afford polymer TEG-N2200 (Figure 2).31Liu J. Qiu L. Alessandri R. Qiu X. Portale G. Dong J. Talsma W. Ye G. Sengrian A.A. Souza P.C.T. et al.Enhancing molecular n-type doping of donor–acceptor copolymers by tailoring side chains.Adv. Mater. 2018; 30: 1704630Crossref Scopus (107) Google Scholar It was found that the polar side chain could greatly suppress the dopant aggregation and improve miscibility with the host matrix. As a result, TEG-N2200 yielded a 200-fold σ (0.17 S cm−1) compared with that of N2200. PDIs showed great successes in both OTFTs and OSCs, but PDI polymers received much less attention than their NDI counterparts mainly because their backbone is more twisted (50°–70°) as a result of severe steric hindrance in the PDI bay region. This limits π-electron delocalization and interchain π-π interactions, yielding low μes in OTFTs.13Sun H. Wang L. Wang Y. Guo X. Imide-functionalized polymer semiconductors.Chem. Eur. J. 2019; 25: 87-105Crossref PubMed Scopus (41) Google Scholar Hence, optimization design principles to planarize PDI polymers are similar to those of the NDI counterparts. For instance, Zhao and co-workers introduced vinylene linkers into the PDI polymer and improved backbone planarity and π-π stacking efficiency. Thus, polymer PDI-V (Figure 2) exhibited a high PCE of 7.57% in all-PSCs,32Guo Y. Li Y. Awartani O. Zhao J. Han H. Ade H. Zhao D. Yan H. A Vinylene-bridged perylenediimide-based polymeric acceptor enabling efficient all-polymer solar cells processed under ambient conditions.Adv. Mater. 2016; 28: 8483-8489Crossref PubMed Scopus (172) Google Scholar which is much higher than those of the linker-free ones and N2200 paired with the same donor (5.3%). Despite some success, the intrinsic twisted backbone and localized LUMO of rylene diimide-based polymers are the two major factors limiting further improvement of device performance. Among various imide-functionalized (hetero)arenes, the bithiophene diimide (BTI) has been proven to be an excellent one. The compact five-membered thiophenes and the imide functionality bridged on bithiophene significantly alleviate steric demand. Additionally, the unfunctionalized thiophene β-positions of BTI offer excellent opportunities for further backbone expansion and core modification.13Sun H. Wang L. Wang Y. Guo X. Imide-functionalized polymer semiconductors.Chem. Eur. J. 2019; 25: 87-105Crossref PubMed Scopus (41) Google Scholar Osaka and co-workers first reported the fused BTI dimer TBI33Saito M. Osaka I. Suda Y. Yoshida H. Takimiya K. Dithienylthienothiophenebisimide, a versatile electron-deficient unit for semiconducting polymers.Adv. Mater. 2016; 28: 6921-6925Crossref PubMed Scopus (67) Google Scholar (also known as f-BTI234Wang Y. Yan Z. Guo H. Uddin M.A. Ling S. Zhou X. Su H. Dai J. Woo H.Y. Guo X. Effects of bithiophene imide fusion on the device performance of organic thin-film transistors and all-polymer solar cells.Angew. Chem. Int. Ed. 2017; 56: 15304-15308Crossref PubMed Scopus (102) Google Scholar), and Guo and co-workers further expanded the BTI family by designing and synthesizing a series of fused BTI oligomers (BTIn) up to 5 imide functionalities and 15 rings in a row.35Wang Y. Guo H. Ling S. Arrechea-Marcos I. Wang Y. López Navarrete J.T. Ortiz R.P. Guo X. Ladder-type heteroarenes: up to 15 rings with five imide groups.Angew. Chem. Int. Ed. 2017; 56: 9924-9929Crossref PubMed Scopus (69) Google Scholar The invention of BTIn greatly enriched the library of imide-functionalized (hetero)arenes and offered a remarkable platform to expand the application of n-type polymers for various devices. Strategies including core substitution, ring fusion, terpolymeriztion, and side-chain engineering have been carried out.36Shi Y. Wang Y. Guo X. Recent progress of imide-functionalized n-type polymer semiconductors.Acta Polym. Sinica. 2019; 50: 873-889Google Scholar All-acceptor (or acceptor-acceptor [A-A])-type polymers are desired for unipolar n-type OTFTs because of both low-lying LUMO and highest occupied molecular orbital (HOMO) levels. However, developing such A-A polymers is very challenging because of the limited A units, significant steric hindrance between neighboring A units, and the less effective polymerization strategies; thus, μes of these polymers is generally < 0.1 cm2 V−1 s−1.13Sun H. Wang L. Wang Y. Guo X. Imide-functionalized polymer semiconductors.Chem. Eur. J. 2019; 25: 87-105Crossref PubMed Scopus (41) Google Scholar Recently, Shi et al. developed the novel thiazolothienyl imide homopolymer PDTzTI (Figure 2) by embedding nitrogen atoms into the thiophene β-positions of BTI, enabling a greatly improved μe (1.61 cm2 V−1 s−1) for A-A polymers.37Shi Y. Guo H. Qin M. Zhao J. Wang Y. Wang H. Wang Y. Facchetti A. Lu X. Guo X. Thiazole imide-based all-acceptor homopolymer: achieving high-performance unipolar electron transport in organic thin-film transistors.Adv. Mater. 2018; 30: 1705745Crossref Scopus (97) Google Scholar This polymer architecture is also beneficial for overcoming Coulomb interaction in the doped state for OTEs. As a result, the doped PDTzTI yielded greatly improved charge generation, which in combination with its high mobility contributed to a remarkable σ of 4.6 S cm−1 and a PF of 7.6 μW m−1 K−2, much higher than those of NDI polymers.38Liu J. Shi Y. Dong J. Nugraha M.I. Qiu X. Su M. Chiechi R.C. Baran D. Portale G. Guo X. et al.Overcoming coulomb interaction improves free-charge generation and thermoelectric properties for n-doped conjugated polymers.ACS Energy Lett. 2019; 4: 1556-1564Crossref Scopus (43) Google Scholar Driven by the success of PDTzTI, a series of (semi)ladder-type BTIn-based A-A homopolymers were also synthesized. Among them, a μe as high as 3.71 cm2 V−1 s−1 was attained from PBTI1 in a OTFT device (Figure 2).39Wang Y. Guo H. Harbuzaru A. Uddin M.A. Arrechea-Marcos I. Ling S. Yu J. Tang Y. Sun H. López Navarrete J.T. et al.(Semi)ladder-type bithiophene imide-based all-acceptor semiconductors: synthesis, structure-property correlations, and unipolar n-type transistor performance.J. Am. Chem. Soc. 2018; 140: 6095-6108Crossref PubMed Sco" @default.
• W3035670900 created "2020-06-19" @default.
• W3035670900 creator A5034118170 @default.
• W3035670900 creator A5055968109 @default.
• W3035670900 creator A5084062631 @default.
• W3035670900 date "2020-06-01" @default.
• W3035670900 modified "2023-10-13" @default.
• W3035670900 title "High-Performance n-Type Polymer Semiconductors: Applications, Recent Development, and Challenges" @default.
• W3035670900 cites W2005306164 @default.
• W3035670900 cites W2022662737 @default.
• W3035670900 cites W2031282918 @default.
• W3035670900 cites W2054300467 @default.
• W3035670900 cites W2066406411 @default.
• W3035670900 cites W2068839774 @default.
• W3035670900 cites W2114235535 @default.
• W3035670900 cites W2149722570 @default.
• W3035670900 cites W2151904002 @default.
• W3035670900 cites W2161208726 @default.
• W3035670900 cites W2162023340 @default.
• W3035670900 cites W2239610429 @default.
• W3035670900 cites W2261606665 @default.
• W3035670900 cites W2264885024 @default.
• W3035670900 cites W2270253191 @default.
• W3035670900 cites W2273029215 @default.
• W3035670900 cites W2313748567 @default.
• W3035670900 cites W2314416268 @default.
• W3035670900 cites W2317025738 @default.
• W3035670900 cites W2319394593 @default.
• W3035670900 cites W2326117367 @default.
• W3035670900 cites W2398786309 @default.
• W3035670900 cites W2403634190 @default.
• W3035670900 cites W2412358867 @default.
• W3035670900 cites W2511010510 @default.
• W3035670900 cites W2515655481 @default.
• W3035670900 cites W2540597880 @default.
• W3035670900 cites W2560688678 @default.
• W3035670900 cites W2587730986 @default.
• W3035670900 cites W2755209080 @default.
• W3035670900 cites W2758165451 @default.
• W3035670900 cites W2767877717 @default.
• W3035670900 cites W2778076912 @default.
• W3035670900 cites W2782882221 @default.
• W3035670900 cites W2784119484 @default.
• W3035670900 cites W2790474173 @default.
• W3035670900 cites W2792783390 @default.
• W3035670900 cites W2794572264 @default.
• W3035670900 cites W2796619249 @default.
• W3035670900 cites W2809115793 @default.
• W3035670900 cites W2810461890 @default.
• W3035670900 cites W2889095573 @default.
• W3035670900 cites W2892166846 @default.
• W3035670900 cites W2895327494 @default.
• W3035670900 cites W2899961247 @default.
• W3035670900 cites W2901220033 @default.
• W3035670900 cites W2904790099 @default.
• W3035670900 cites W2909990379 @default.
• W3035670900 cites W2912263054 @default.
• W3035670900 cites W2913356609 @default.
• W3035670900 cites W2916664629 @default.
• W3035670900 cites W2948464847 @default.
• W3035670900 cites W2948773749 @default.
• W3035670900 cites W2951464486 @default.
• W3035670900 cites W2952137439 @default.
• W3035670900 cites W2963692062 @default.
• W3035670900 cites W2965542694 @default.
• W3035670900 cites W2970396538 @default.
• W3035670900 cites W2973805763 @default.
• W3035670900 cites W2979065434 @default.
• W3035670900 cites W2981555465 @default.
• W3035670900 cites W2982063376 @default.
• W3035670900 cites W2989803300 @default.
• W3035670900 cites W2990105054 @default.
• W3035670900 cites W2992432539 @default.
• W3035670900 cites W2994604100 @default.
• W3035670900 cites W2996794239 @default.
• W3035670900 cites W2998826655 @default.
• W3035670900 cites W3006013311 @default.
• W3035670900 cites W3006564812 @default.
• W3035670900 cites W3007098444 @default.
• W3035670900 cites W3012409835 @default.
• W3035670900 cites W3106256620 @default.
• W3035670900 cites W4239394999 @default.
• W3035670900 cites W4240721961 @default.
• W3035670900 cites W4254183062 @default.
• W3035670900 doi "https://doi.org/10.1016/j.chempr.2020.05.012" @default.
• W3035670900 hasPublicationYear "2020" @default.
• W3035670900 type Work @default.
• W3035670900 sameAs 3035670900 @default.
• W3035670900 citedByCount "202" @default.
• W3035670900 countsByYear W30356709002020 @default.
• W3035670900 countsByYear W30356709002021 @default.
• W3035670900 countsByYear W30356709002022 @default.
• W3035670900 countsByYear W30356709002023 @default.
• W3035670900 crossrefType "journal-article" @default.
• W3035670900 hasAuthorship W3035670900A5034118170 @default.
• W3035670900 hasAuthorship W3035670900A5055968109 @default.
• W3035670900 hasAuthorship W3035670900A5084062631 @default.
• W3035670900 hasBestOaLocation W30356709001 @default.

• next