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。     

掺杂在有机场效应晶体管中的应用进展

有机场效应晶体管(OFETs)作为一种新型的电子器件,以其柔性、可大规模简单制备等优势获得了广泛的关注。 但是,OFETs面临着器件性能不足、调控手段复杂等问题。人们尝试使用掺杂对这些问题加以解决。 本文结合本课题组的相关工作,对掺杂技术在OFETs上的应用进行归纳、总结和展望。     

全小分子有机太阳能电池：多级次形貌调控实现效率突破

正有机本体异质结(BHJ)太阳能电池由于其质轻和可大面积印刷柔性器件等优势而引起了广泛的关注。小分子给体具有分子量明确、易于纯化和批次差异小等优点。此外,小分子较强的结晶性可以获得更高的相纯度和更低的能量无序度,从而可制备高电荷迁移率、低能量损失的有机太阳能     

柔性纤维生物电子复合材料与器件

可穿戴和可植入的纤维生物电子器件可以实现对人体生理体征的实时监测和精准调控,在健康监测和疾病诊疗等领域发挥了革新作用.然而,传统的纤维生物电子器件柔性不足而与生物软组织的力学性能不匹配,难以形成稳定的器件/组织界面,最终无法实现长期稳定工作.本文重点介绍了近年来课题组针对上述问题在柔性纤维生物电子复合材料与器件方面的研究进展.首先制备了具有杂化结构和芯鞘结构的柔性高分子复合纤维电极,并面向柔性生物电子器件要求,对纤维材料的电学和力学性能及生物安全性进行表征.进一步,基于所制备的复合纤维电极,发展出一系列可穿戴和可植入的纤维生物电子器件,具有传感、能源、调控等功能,并通过建立稳定的器件/组织界面,实现了在体长期工作,在生物医学研究和智慧医疗等领域展现出良好的应用前景.最后,展望了柔性纤维生物电子领域的未来发展方向.     

有机光伏研究进展

以有机半导体材料为活性层的有机太阳能电池, 可通过印刷制备大面积柔性器件, 具有成本低、多彩、半透明等特点, 是一种极具发展前景的光伏技术. 研究者们多年来致力于设计高性能光伏材料, 优化器件界面, 改善活性层微观形貌, 开发新型器件结构, 探究器件工作机理等, 目前实验室制备的小面积有机太阳能电池的能量转换效率已经超过18%. 另外, 面向有机光伏产业化, 在制备大面积柔性器件、降低器件成本、提高器件寿命以及探究光伏建筑一体化和室内光伏等潜在应用方面的研究也取得了重要进展, 在国际上处于领跑地位. 中国科学家在有机光伏领域做出了诸多开创性和引领性的工作. 本文首先对有机太阳能电池的背景进行简单介绍, 接着按照分子工程、器件工程、器件物理和应用探索四个方面综述有机光伏领域的重要研究进展, 最后对有机光伏所面临的机遇与挑战进行展望.     

并五苯及其衍生物在有机场效应晶体管中的应用

有机场效应晶体管（organic field—effect transistors,OFETs）是以有机半导体材料作为有源层,通过电场控制电流的电子器件．与传统的无机半导体器件相比,由于其可应用于生产大面积、柔性、低成本电子设备而备受关注,在有机存储器件、有机太阳能电池、柔性平板显示和电子纸等众多领域具有潜在而广泛的应用前景．并苯类材料因其紧密的分子堆积及优异的半导体性能被广泛研究．其中,并五苯及其衍生物在场效应晶体管中表现出良好的性质,其效果甚至可以与非晶硅相媲美,但并五苯较差的溶解性及环境稳定性阻碍了其进一步应用．科研工作者通过对分子结构进行修饰改造设计,合成了一系列并五苯的衍生物,其不仅在稳定性、电学性能和溶解性方面有很大提高,还可以将该p-型半导体材料拓展到双极性及n-型半导体材料领域．本文对并五苯及其衍生物在有机场效应晶体管中的应用进行了较为全面的综述,期望对该领域的研究起到一定的推动作用．     

溶液法大面积制备有机小分子场效应晶体管

作为柔性电子器件的基本构筑元件,有机场效应晶体管(OFETs)近年来受到深入研究并在高性能材料研发和器件多功能应用等方面取得了长足的进展。溶液加工技术以其温和的操作条件和灵活多样的工艺流程,成为实现高性能有机场效应晶体管器件低成本、大面积制备的优良选择。与聚合物相比,小分子有机半导体材料具有较高的固态堆积有序度及紧密程度和材料纯度,更易加工出性能优良的器件。然而小分子材料的成膜性较差,溶液加工潜能欠佳。如何通过不同的溶液加工技术制备取向均一的大面积连续小分子半导体薄膜,进而构筑高性能大面积器件阵列,成为了领域内的研究重点。本文概述了近年来可溶液加工且性能优良的小分子有机半导体材料研究进展,并依据工艺特点,分别介绍了溶液滴注、弯液面引导涂布和打印这三类可实现大面积制备的溶液加工技术,最后对溶液法大面积制备有机小分子场效应晶体管领域的发展前景进行了展望。     

柔性电子学中的表界面化学

柔性电子作为新兴的研究热点, 涉及材料、 化学、 物理等多个基础学科的交叉, 以及在生物医用、 可穿戴设备及人工智能等多个领域的应用. 柔性电子设备的制造加工过程中会用到弹性基底、 导电层、 功能层等多种性质各异的材料, 其互相之间的整合受到它们表面性质和界面结合力的限制; 器件的功能、 可靠性、 对环境的敏感性等也受到了器件表界面性质的影响; 因此, 对材料和器件表界面的处理在柔性电子学中具有重要作用. 本文对柔性电子学中常用的表界面化学过程分为3大类进行介绍: 表面电化学过程, 基于特定化合物反应产生的电流制备电化学传感器, 利用电流/电压控制表面负载化合物; 表面修饰, 通过表面改性提高材料的加工性能, 共价修饰分子层或其它材料赋予器件特殊功能性质或保护层; 不同材料之间的界面连接, 通过共价连接或化学反应辅助的物理交联实现不同材料的结合, 提高柔性器件的稳定性, 实现柔性设备的整合. 对各应用进行总结和举例后, 讨论了存在的问题, 并对未来的发展方向及前景进行了展望.     

基于有机(高分子)半导体和光致变色分子的场效应晶体管

作为有机电子学重要的研究内容,有机场效应晶体管(OFETs)的研究近年来得到了广泛的关注.随着应用场景的多元化,研究者对具有多功能,尤其是对特定外场刺激具有响应及存储功能的场效应晶体管的研究越来越重视.其中,在光照下发生器件性能可逆变化的有机场效应晶体管在神经突触模拟、多稳态记忆器件、非易失性存储器等功能器件领域具有潜...     

一种高容量茴香状硫化铜柔性电极的制备及其在超级电容器中的应用

柔性电极由于在可穿戴电子设备领域具有重要应用而备受关注，然而其制备工艺繁琐、价格昂贵、负载量低和比容量低等问题限制了其发展.为解决这些问题，迫切需要开发负载量大、比容量高的柔性电极材料.本文利用简单的化学电镀和低温固相反应方法，制备了茴香状的CuS@CPCC-24柔性电极材料.这种紧密堆砌的薄片具有大量的孔隙，能够提供足够的活性位点，进而有效增加存储电荷的能力.结果表明，CuS@CPCC-24柔性电极不仅在电流密度为2 mA·cm^-2时可达到1 150.2 mF·cm^-2的最大电容，而且循环稳定性较好，展现了其在柔性储能器件领域具有潜在应用.     

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...     

Photoresponsive n-channel organic field-effect transistors based on a tri-component active layer

Photoresponsive OFETs were fabricated based on a tri-component active layer (NDI2OD-DTYM2, spiropyran and polystyrene). The results demonstrated that these OFETs displayed photoresponsive feature to alternate UV and vis light due to the photoisomerization of spiropyran between the closed-ring state and ionic open-ring state.     

Ladder‐Type Heteroarene‐Based Organic Semiconductors

The fusion of heteroaromatic rings into ladder‐type heteroarenes can stabilize frontier molecular orbitals and lead to improved physicochemical properties that are beneficial for applications in various optoelectronic devices. Thus, ladder‐type heteroarenes, which feature highly planar backbones and well‐delocalized π conjugation, have recently emerged as a promising type of organic semiconductor with excellent device performance in organic photovoltaics (OPVs) and organic field‐effect transistors (OFETs). In this Focus Review, we summarize the recent advances in ladder‐type heteroarene‐based organic semiconductors, such as hole‐ and electron‐transporting molecular semiconductors, and fully ladder‐type conjugated polymers towards their applications in OPVs and OFETs. The recent use of ladder‐type small‐molecule acceptor materials has strikingly boosted the power conversion efficiency of fullerene‐free solar cells, and selected examples of the latest developments in ladder‐type fused‐ring electron acceptor materials are also elaborated.     

A General Method for Growing Two‐Dimensional Crystals of Organic Semiconductors by “Solution Epitaxy”

Two‐dimensional (2D) crystals of organic semiconductors (2DCOS) have attracted attention for large‐area and low‐cost flexible optoelectronics. However, growing large 2DCOS in controllable ways and transferring them onto technologically important substrates, remain key challenges. Herein we report a facile, general, and effective method to grow 2DCOS up to centimeter size which can be transferred to any substrate efficiently. The method named “solution epitaxy” involves two steps. The first is to self‐assemble micrometer‐sized 2DCOS on water surface. The second is epitaxial growth of them into millimeter or centimeter sized 2DCOS with thickness of several molecular layers. The general applicability of this method for the growth of 2DCOS is demonstrated by nine organic semiconductors with different molecular structures. Organic field‐effect transistors (OFETs) based on the 2DCOS demonstrated high performance, confirming the high quality of the 2DCOS.     

Monolayer organic field-effect transistors

Monolayer organic field-effect transistors(OFETs) are attracting worldwide interest in device physics and novel applications due to their ultrathin active layer for two-dimensional charge transport. The monolayer films are generally prepared by thermal evaporation, the Langmuir technique or self-assembly process, etc., but their electrical performance is relatively lower than corresponding thick films. From 2011, the performance of monolayer OFETs has been boosted by using the monolayer molecular crystals(MMCs) as active channels, which opened up a new era for monolayer OFETs. In this review, recent progress of monolayer OFETs, including the preparation of monolayer films, their OFET performance and applications are summarized.Finally, perspectives of monolayer OFETs in the near future are also discussed.     

Strongly Correlated Alignment of Fluorinated 5,11‐Bis(triethylgermylethynyl)anthradithiophene Crystallites in Solution‐Processed Field‐Effect Transistors

The crystallinity of an organic semiconductor film determines the efficiency of charge transport in electronic devices. This report presents a micro‐to‐nanoscale investigation on the crystal growth of fluorinated 5,11‐bis(triethylgermylethynyl)anthradithiophene (diF‐TEG‐ADT) and its implication for the electrical behavior of organic field‐effect transistors (OFETs). diF‐TEG‐ADT exhibits remarkable self‐assembly through spin‐cast preparation, with highly aligned edge‐on stacking creating a fast hole‐conducting channel for OFETs.     

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.     

Multilevel Nonvolatile Flexible Organic Field‐Effect Transistor Memories Employing Polyimide Electrets with Different Charge‐Transfer Effects

The electrical memory characteristics of the n‐channel organic field‐effect transistors (OFETs) employing diverse polyimide (PI) electrets are reported. The synthesized PIs comprise identical electron donor and three different building blocks with gradually increasing electron‐accepting ability. The distinct charge‐transfer capabilities of these PIs result in varied type of memory behaviors from the write‐one‐read‐many (WORM) to flash type. Finally, a prominent flexible WORM‐type transistor memory is demonstrated and shows not only promising write‐many‐read‐many (WMRM) multilevel data storage but also excellent mechanical and retention stability.