新型共轭聚合物的设计合成及其在场效应晶体管的应用

近年来,有机场效应晶体管(OFETs)由于在柔性器件和可穿戴电子学中的潜在应用受到了学术界和工业界的普遍关注,尤其是以聚合物半导体材料构筑的晶体管性能得到了快速的发展.如何设计合成用于OFETs的高性能聚合物半导体材料,一直是我们的追求目标.然而,分子结构对迁移率的影响仍缺少系统的比较.本文综述了近年来国内外新型聚合物材料的最新进展.我们按照材料的种类以及载流子的传输类型进行了分类,对高性能聚合物材料的发展过程、材料的设计思路以及相应的FETs性能进行了系统地归纳总结.通过研究分子及分子聚集态结构与器件性能之间的关系,希望为以后设计合成新型的高性能的聚合物材料提供有益的借鉴和指导.     

Semiconducting Polymers Based on Simple Electron-Deficient Cyanated trans-1,3-Butadienes for Organic Field-Effect Transistors

Developing high-performance but low-cost n-type polymers remains a significant challenge in the commercialization of organic field-effect transistors (OFETs). To achieve this objective, it is essential to design the key electron-deficient units with simple structures and facile preparation processes, which can facilitate the production of low-cost n-type polymers. Herein, by sequentially introducing fluorine and cyano functionalities onto trans-1,3-butadiene, we developed a series of structurally simple but highly electron-deficient building blocks, namely 1,4-dicyano-butadiene ( CNDE ), 3-fluoro-1,4-dicyano-butadiene ( CNFDE ), and 2,3-difluoro-1,4-dicyano-butadiene ( CNDFDE ), featuring a highly coplanar backbone and deep-positioned lowest unoccupied molecular orbital (LUMO) energy levels (−3.03–4.33 eV), which render them highly attractive for developing n-type semiconducting polymers. Notably, all these electron-deficient units can be easily accessed by a two-step high-yield synthetic procedure from low-cost raw materials, thus rendering them highly promising candidates for commercial applications. Upon polymerization with diketopyrrolopyrrole ( DPP ), three copolymers were developed that demonstrated unipolar n-type transport characteristics in OFETs with the highest electron mobility of >1 cm² V⁻¹ s⁻¹. Hence, CNDE , CNFDE , and CNDFDE represent a class of novel, simple, and efficient electron-deficient units for constructing low-cost n-type polymers, thereby providing valuable insight for OFET applications.     

Rational design of diarylethylene-based polymeric semiconductors for high-performance organic field-effect transistors

Constructing planar, rigid, and high electronically delocalized π-conjugated molecular system is the most basic requirements of obtaining high-performance polymeric semiconductors for organic field-effect transistors (OFETs). In this regard, diarylethylene (DAE)-based polymers show great potential because many substantive progresses related to polymer field-effect transistors had been achieved from the kind of polymer materials in recent years. In the brief review, series of DAE-based polymer are highlighted, based on which several design strategies have been summarized by the way of comparative research method. These strategies have important guiding significance not only for further developing new DAE-based and other polymeric semiconductors for OFETs but also for developing specific polymeric semiconductors for other organic electronics, such as organic photovoltaics and organic light-emitting diodes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 585–603     

Organic transistors in the new decade: Toward n-channel,printed, and stabilized devices

Significant progress has been made in designing organic semiconducting materials (OSCs) for the past few decades for organic field-effect transistors (OFETs). Much attention has been paid to the development of p-channel OSCs, with less but highly significant progress on n-channel OSCs. In this review, we focus on the advances made with OFETs in the last few years to achieve high performance in n-channel modes, air stability, and solution processability, leading to printable active electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

Functionalized Phenanthrene Imide-Based Polymers for n-Type Organic Thin-Film Transistors

High-performing n-type polymers are crucial for the advance of organic electronics field, however strong electron-deficient building blocks with optimized physicochemical properties for constructing them are still limited. The imide-functionalized polycyclic aromatic hydrocarbons ( PAH s) with extended π-conjugated framework, high electron deficiency and good solubility serve as promising candidates for developing high-performance n-type polymers. Among the PAH s, phenanthrene ( PhA ) features a well-delocalized aromatic π-system with multiple modifiable active sites . However, the PhA -based imides are seldom studied, mainly attributed to the synthetic challenge. Herein, we report two functionalized PhA s, CPOI and CPCNI , by simultaneously incorporating imide with carbonyl or dicyanomethylene onto PhA . Notably, the dicyanomethylene-modified CPCNI exhibits a well stabilized LUMO energy level (−3.84 eV), attributed to the synergetic inductive effect from imide and cyano groups. Subsequently, based on CPOI and CPCNI , two polymers PCPOI-Tz and PCPCNI-Tz were developed. Applied to organic thin-film transistors, owing to the strong electron-deficiency of CPCNI , polymer PCPCNI-Tz shows an improved electron mobility and largely decreased threshold voltage compared with PCPOI-Tz . This work affords two structurally novel electron-deficient building blocks and highlights the effectiveness of dual functionalization of PhA s with strong electron-withdrawing groups for devising n-type polymers.     

Electron transporting semiconducting polymers in organic electronics

Significant progress has been achieved in the preparation of semiconducting polymers over the past two decades, and successful commercial devices based on them are slowly beginning to enter the market. However, most of the conjugated polymers are hole transporting, or p-type, semiconductors that have seen a dramatic rise in performance over the last decade. Much less attention has been devoted to electron transporting, or n-type, materials that have lagged behind their p-type counterparts. Organic electron transporting materials are essential for the fabrication of organic p-n junctions, organic photovoltaic cells (OPVs), n-channel organic field-effect transistors (OFETs), organic light-emitting diodes (OLEDs) and complementary logic circuits. In this critical review we focus upon recent developments in several classes of electron transporting semiconducting polymers used in OLEDs, OFETs and OPVs, and survey and analyze what is currently known concerning electron transporting semiconductor architecture, electronic structure, and device performance relationships (87 references).     

有机场效应晶体管应用于化学及生物传感的研究进展

有机场效应晶体管(OFETs)是以有机半导体材料作为有源层的晶体管器件。和传统的无机半导体器件相比,由于其具有成本低、易加工、柔性好和生物相容性而被人们广泛研究,在多种化学和生物传感器领域具有潜在而广泛的应用前景。本文简单介绍了OFETs的结构和工作原理,总结了近几年来OFETs在化学及生物传感方面的研究进展,最后对OFETs的发展方向做了归纳和展望。     

Proteins as functional interlayer in organic field-effect transistor

The paper summarizes and discusses the recent advances of proteins as functional interlayers in organic field-effect transistors (OFETs). Specific focus is given on the proteins integrated into the device structure, either to act as dielectric materials or to perform as the functional interlayer between the dielectric and the organic semiconductor (OSC). The main emphasis is give to the location and the specific effect of protein layers in the structure of OFETs. Besides, the possibility of amyloid serving as useful building blocks for OFET is discussed.     

Angular-shaped naphthalene tetracarboxylic diimides for n-channel organic transistor semiconductors

A series of compounds based on the angular-shaped naphthalene tetracarboxylic diimide core have been synthesized, characterized and used as active layers of organic field-effect transistors (OFETs). The fabricated OFET devices exhibit n-type semiconducting characteristics, demonstrating the first examples of semiconductors based on angular-shaped naphthalene tetracarboxylic diimides.     

Corannulene derivatives for organic electronics: From molecular engineering to applications

This paper intends to provide an overview for using corannulene derivatives in organic electronics such as organic field-effect transistors (OFETs), organic solar cells (OSCs), and organic light-emitting diodes (OLEDs). We highlight the rational design strategies, tuning molecular orbital energy levels and arrangement in single crystals of corannulenes. The topological structure and properties of corannulene make it a unique candidate for organic electronics.     

High-performance and multifunctional organic field-effect transistors

Organic field-effect transistors(OFETs) refer to field-effect transistors that use organic semiconductors as channel materials. Owing to the advantages of organic materials such as solution processability and intrinsic flexibility, OFETs are expected to be applicable in emergent technologies including wearable electronics and sensors, flexible displays, internet-of-things, neuromorphic computing, etc. Improving the electrical performance and developing multifunctionalities of OFETs are two major...     

Recent development of perylene diimide-based small molecular non-fullerene acceptors in organic solar cells

This review summarizes the recent progress of perylene diimide (PDI) derivatives used as the acceptor materials in non-fullerene organic solar cells. The resulting structure-property correlations and design strategies of this type of acceptors are discussed and commented, which will help to constructing high-performance PDI-based acceptor materials in the future. The problems at present and the effort direction are also pointed out in this review.     

Tailoring and patterning of dielectric interfaces for the development of advanced organic field-effect transistors

The progress of organic field-effect transistors (OFETs) has led to the advent of a new area of printed and/or flexible electronics. In organic transistors and circuits, the interface between a gate insulator (GI) and an organic semiconductor (OS) plays a critical role on the electrical performance together with the functionality, the reliability and the long-term stability. In this review, we describe the basic principles of engineering a variety of the GI/OS interfaces for the development of advanced OFETs from the framework of the surface morphology and the physico-chemical surface interactions. We also discuss the dielectric interface modification and the resultant device performance of the OFETs.     

Noncovalent conformational locks in organic semiconductors

Highly planar conformation is considered to be one of the most important properties for high performance organic semiconductors. Among all kinds strategies for designing highly performing materials, noncovalent conformational locks(NCLs)have been widely used to increase the planarity and rigidity for π-conjugated systems. This review summarizes π-conjugated small molecules and polymers by employing various NCLs for controlling molecular conformation in the past two years. The optoelectronic properties of the conjugated materials, together with their applications on organic field-effect transistors(OFETs)and organic photovoltaics(OPVs) are discussed. Besides, the outlook and challenges in this field are also presented. It is obvious that NCLs play an important role in the design and synthesis of high-performance organic semiconductors.     

Progresses in organic field-effect transistors and molecular electronics

In the past years, organic semiconductors have been extensively investigated as electronic materials for organic field-effect transistors (OFETs). In this review, we briefly summarize the current status of organic field-effect transistors including materials design, device physics, molecular electronics and the applications of carbon nanotubes in molecular electronics. Future prospects and investigations required to improve the OFET performance are also involved. __________ Translated from Huaxue Tongbao (Chemistry), 2006, 69(6) (in Chinese)     

Rylene diimide and dithienocyanovinylene copolymers for polymer solar cells

Two polymers containing(E)-2,3-bis(thiophen-2-yl)acrylonitrile(CNTVT) as a donor unit, perylene diimide(PDI) or naphthalene diimide(NDI) as an acceptor unit, are synthesized by the Stille coupling copolymerization, and used as the electron acceptors in the solution-processed organic solar cells(OSCs). Both polymers exhibit broad absorption in the region of 300–850 nm. The LUMO energy levels of the resulted polymers are ca. –3.93 eV and the HOMO energy levels are –5.97 and –5.83 eV. In the binary blend OSCs with PTB7-Th as a donor, PDI polymer yields the power conversion efficiency(PCE) of up to 1.74%, while NDI polymer yields PCE of up to 3.80%.     

The impact of regiochemistry of conjugated molecules on the performance of organic electronic devices

Organic photovoltaics and field-effect transistors have attracted considerable attention due to the easy fabrication,low cost,light weight,and flexibility.Unsymmetrical conjugated building blocks are widely utilized for the design of new organic π-functional materials in order to achieve high-performance electronic devices,which has become a hot research topic in recent years.In this review,we summarized some typical organic π-functional materials with regioregular conjugated backbones with unsymmetrical electron-deficiency moieties and focused on the influence of regiochemistry on the final device performance.     

High-performance organic field-effect transistors: molecular design, device fabrication, and physical properties

In the past decade, tremendous progress has been made in organic field-effect transistors (OFETs). Their real applications require further development of device performance. OFETs consist of organic semiconductors, dielectric layers, and electrodes. Organic semiconductors play a key role in determining the device characteristics. The properties of the organic semiconductors, such as molecular structure and packing, as well as molecular energy levels, can be properly controlled by molecular design. Therefore, we designed and synthesized a series of organic molecules. The synthesized organic semiconductors exhibit excellent field-effect properties due to strong intermolecular interactions and proper molecular energy levels. Meanwhile, the influence of the device fabrication process, organic semiconductor/dielectric layer interface, and organic layer/electrode contact on the device performance was investigated. A deep understanding of these factors is helpful to improve field-effect properties. Furthermore, single-crystal field-effect transistors are highlighted because the single-crystal-based FETs can provide an accurate conducting mechanism of organic semiconductors and higher device performance as compared with thin film FETs.     

Halogenated 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene: applications for ambipolar air-stable organic field-effect transistors

Density functional theory calculations were performed to explore the influence of halogenation on the reorganization energies (λ), adiabatic ionization potentials (IPs), adiabatic electron affinities (EAs), and air stabilities of a series of pentacene (PENT) and tetraceno[2,3-b]thiophene (TbTH) derivatives. According to calculated IP and EA values, all well-known PENT and TbTH derivatives in this paper are air-stable p-channel but not air-stable n-channel organic field-effect transistors (OFETs) due to insufficient EAs, consistent with experimental observations. The calculated results show that attaching two or more halogen atoms onto air-unstable 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene (TIPS-N4PENT) is sufficient for promoting ambipolar air-stable properties. The electronic coupling and band structure calculations indicate that halogenated TIPS-N4PENT derivatives have potential applications in high-performance ambipolar air-stable OFETs. They also provide rational guidelines for the design of ambipolar air-stable organic semiconductors (OSCs).     

Imide-Functionalized Polymer Semiconductors

Imide-functionalized π-conjugated polymer semiconductors have received a great deal of interest owing to their unique physicochemical properties and optoelectronic characteristics, including excellent solubility, highly planar backbones, widely tunable band gaps and energy levels of frontier molecular orbitals, and good film morphology. The organic electronics community has witnessed rapid expansion of the materials library and remarkable improvement in device performance recently. This review summarizes the development of imide-functionalized polymer semiconductors as well as their device performance in organic thin-film transistors and polymer solar cells, mainly achieved in the past three years. The materials mainly cover naphthalene diimide, perylene diimide, and bithiophene imide, and other imide-based polymer semiconductors are also discussed. The perspective offers our insights for developing new imide-functionalized building blocks and polymer semiconductors with optimized optoelectronic properties. We hope that this review will generate more research interest in the community to realize further improved device performance by developing new imide-functionalized polymer semiconductors.