Opto-electronic polymers for advanced computer and communication technologies

This paper describes reviews about the characterization of optical and electronic (opto-electronic) organic materials including polymers, and their applications for advanced key devices used for computers and communications technologies. On the basis of the author's recent investigations, discussions are made on organic electroluminescent thin film materials for emissive display devices, polymer-dispersed liquid crystal materials for passive display devices, organic photo-conductive materials for electrophotographic printer devices, and highly electroconductive polymers for solid tantalum capacitors. Finally, technical issues and development prospects for the opto-electronic organic materials in the 21st century are suggested.     

Organometallic chemistry related to applications for microelectronics in Japan

This is meant to be a brief overview of the developments of research activities in Japan on organometallic compounds related to their use in electronic and optoelectronic devices. The importance of organometallic compounds in the deposition of metal and semiconductor films for the fabrication of many electronic and opto-electronic devices cannot be exaggerated. Their scope has now extended to thin-film electronic ceramics and high-temperature oxide superconductors. A variety of organometallic compounds have been used as source materials in many types of processing procedures, such as metal–organic chemical vapor deposition (MOCVD), metalorganic vapor-phase epitaxy (MOVPE), metal–organic molecular-beam epitaxy (MOMBE), etc. Deposited materials include silicon, Group III–V and II–VI compound semiconductors, metals, superconducting oxides and other inorganic materials. Organometallic compounds are utilized as such in many electronic and optoelectronic devices; examples are conducting and semiconducting materials, photovoltaic, photochromic, electrochromic and nonlinear optical materials. This review consists of two parts: (I) research related to the fabrication of semiconductor, metal and inorganic materials; and (II) research related to the direct use of organometallic materials and basic fundamental research.     

Functionalization of mesostructured inorganic–organic and porous inorganic materials

The capability to functionalize the interior channels and/or high internal surface areas of mesostructured inorganic–organic or porous inorganic solids with specific organic or inorganic moieties has dramatically expanded the potential applications for these versatile materials in catalysis, separations, optical and opto-electronic devices, drug delivery, sensors, and energy conversion. Key to the widespread application of these materials are the various synthetic schemes that have been developed to provide control over the types of species incorporated and, more importantly, their distributions within the mesostructured hosts. Furthermore, multiple active species can often be independently incorporated and collectively optimized to yield multifunctional properties that widen application prospects. Several recent developments and examples in this rapidly growing field of materials chemistry and engineering are highlighted and discussed.     

红色铱配合物磷光材料及器件的研究进展

有机电致发光器件具有驱动电压低、高亮度、高效率等优点,引起了研究人员的广泛关注,在固态照明和平板显示领域具有广阔应用前景。 在绿、蓝、红三基色器件中,绿光器件和蓝光器件的性能普遍优于红光器件,基本满足了产业化的需要;目前红色有机电致发光材料及器件的研究进展相对缓慢。 因为红光材料的能隙较窄,致使主客体材料之间能级匹配困难,导致红光器件普遍效率低、色纯度差,但是,红光材料是获得白光器件必不可少的材料。 因此,如何获得高性能红光材料对于有机电致发光器件的发展至关重要。 本文综述了近年来红色铱配合物磷光材料及器件的研究进展,对提升效率和色纯度的方法进行重点阐述;并结合现有工作,对红色有机电致磷光材料与器件的前景进行展望。     

超支化共轭聚合物的合成、性质及在光电器件中的应用研究进展

简述超支化共轭聚合物光电活性材料研究进展,设计、合成了多种具有3-D立体结构的超支化共轭聚合物,研究了它们的结构与性能的关系及其在器件上的应用.实验结果表明,这种聚合物具有良好的溶解性,可成膜性和高的发光效率.可应用于发光二极管(LED),发光电化学池(LEC),光伏打电池等器件.这类化合物不仅可以作为发光材料,还可以通过修饰得到具有分子或离子识别、信息存储性能的特殊功能材料.     

有机分子电致发光材料进展*

由于有机电致发光器件在彩色平板显示等领域具有极大的应用前景,已引起广泛的关注。与无机物相比,有机发光材料具有高荧光效率、颜色的广泛选择性及易成膜性。本文主要介绍近年来有机分子电致发光材料最新的发展,并特别讨论了齐聚物和含载流子传输单元的发光体。     

氮杂苯并菲类n-型有机半导体材料研究进展

苯并菲盘状液晶是一类新型的有机电子学材料.该类材料多数以空穴传输功能为主,能传输电子的n-型材料较少.氮杂苯并菲是与苯并菲衍生物非常相似的一种杂环化合物,材料结构中引入了氮原子,吸电子能力得到增强,是潜在的n-型有机半导体材料,具有重要的应用价值.本文系统回顾了氮杂苯并菲类盘状液晶材料的研究进展,分类讨论了材料的分子结构,其中包括二、四、六氮杂苯并菲,以及它们的合成方法和物理化学性能,论述了材料在光电子领域的最新使用进展,并在此基础上,对该类液晶材料作为n-型有机半导体在光电子器件领域的应用前景进行了展望.     

Memory devices based on lanthanide (Sm3+, Eu3+, Gd3+) complexes

Memory effects in single-layer organic light-emitting devices based on Sm3+, Gd3+, and Eu3+ rare earth complexes were realized. The device structure was indium-tin-oxide (ITO)/3,4-poly(ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT)/Poly(N-vinyl carbazole) (PVK): rare earth complex/LiF/Ca/Ag. It was found experimentally that all the devices exhibited two distinctive bistable conductivity states in current-voltage characteristics by applying negative starting voltage, and more than 10(6) write-read-erase-reread cycles were achieved without degradation. Our results indicate that the rare earth organic complexes are promising materials for high-density, low-cost memory application besides the potential application as organic light-emitting materials in display devices.     

有机/聚合物顶发射发光器件

有机/聚合物顶发射发光器件可以解决传统底发射发光器件的一系列不足。高性能顶发射发光器件的实现,首先必须优化器件结构,其次对电子注入材料和空穴注入材料提出更高的要求。本文从提高顶发射器件中电子注入和空穴注入方法入手,综述了国内外有机/聚合物顶发射电致发光器件的发展历史,研究现状,最新进展及以后的发展方向。     

ORMOCER®s for Optical Interconnection Technology

New inorganic-organic hybrid polymers (ORMOCER®s) for integrated optical and opto-electronic devices were synthesized by sol-gel processing of functionalized alkoxysilanes. Process parameters (catalyst, temperature etc.) were optimized to achieve highly reproducible low cost materials which are photopatternable even in higher layer thickness (presently 100 m within one step).The resulting materials have low optical losses at the most important wavelengths for telecommunications in the NIR range (0.3 dB/cm at 1320 nm, 0.6 dB/cm at 1550 nm) and a variety of additional advantageous properties for optical interconnection technology and production of opto-electronic devices: good wetting and adhesion on various substrates (e.g. glass, silicon and several polymers), low processing temperatures (post-bake at 150°C) and high thermal stability (decomposition at 270°C) compared to alternative opto-polymers for NIR applications. A further advantage is a tunable refractive index, which can be achieved by mixing different resins.     

Two-dimensional Covalent Organic Frameworks for Electrochromic Switching

The electrochromic materials have received immense attention for the fabrication of smart optoelectronic devices. The alteration of the redox states of the electroactive functionalities results in the color change in response to electrochemical potential. Even though transition metal oxides, redox-active small organic molecules, conducting polymers, and metallopolymers are known for electrochromism, advanced materials demonstrating multicolor switching with fast response time and high durability are of increasing demand. Recently, two-dimensional covalent organic frameworks (2D COFs) have been demonstrated as electrochromic materials due to their tunable redox functionalities with highly ordered structure and large specific surface area facilitating fast ion transport. Herein, we have discussed the mechanistic insights of electrochromism in 2D COFs and their structure-property relationship in electrochromic performance. Furthermore, the state-of-the-art knowledge for developing the electrochromic 2D COFs and their potential application in next-generation display devices are highlighted.     

First-principles approach to the understanding of π-conjugated organic semiconductors

We show how ab initio calculations based on density functional theory contribute to the understanding of the electronic and optical properties of organic semiconducting materials, which form the active layers in many opto-electronic applications. As a textbook example, we present the electronic structure and the optical properties of the oligo-phenylenes as evolving from their benzene-constituents. Thereby we discuss the dependence on the molecular length and introduce the modifications in the opto-electronic properties due to intermolecular interactions which are inherently present in the bulk phase.     

Self-supported bacterial cellulose/boehmite organic–inorganic hybrid films

Self-supported organic-inorganic hybrid transparent films have been prepared from bacterial cellulose and boehmite. SEM results indicate that the BC membranes are covered by Boehmite and XRD patterns suggest structural changes on cellulose due to Boehmite addition. Thermal stability is accessed through TG curves and is dependent on Boehmite content. Transparency, as evaluated by UV?CVis absorption, increases with increasing content of boehmite suggesting application of these materials as transparent substrates for opto-electronic devices.     

Advances in the field of π-conjugated 2,2':6',2"-terpyridines

This critical review summarizes the research progress made in the field of π-conjugated terpyridines within the last decade. Supramolecular materials based on metal ion complexes of 2,2':6',2"-terpyridine derivatives have found manifold potential applications-from opto-electronic devices to life science. In this contribution, synthetic strategies towards π-conjugated terpyridines and their incorporation into advanced supramolecular architectures are evaluated. Applications as photoactive species in, e.g., photovoltaic devices, polymer light-emitting diodes (PLEDSs) and nanotechnology are discussed comprehensively (523 references).     

单分子有机电致白光材料及器件

有机电致白光二极管在白光照明和背光源应用中具有材料来源广、驱动电压低、节能和环保等优点,受到了广泛关注。目前实现电致白光的方法主要有小分子掺杂、多层器件、激基复合物和缔合物发光以及单分子白光等方法。其中,单分子白光材料由于要控制能量的不完全传递、单分子实现多色同步发射和优化器件结构等,目前研究得还比较少,器件的总体性能相对还不是很理想。本文从材料合成的角度,简要综述了国内外在单分子白光材料的合成与器件性能优化方面所取得的研究进展,并对下一步需要研究的热点问题作了展望。     

From electronic excited state theory to the property predictions of organic optoelectronic materials

We introduce here a work package for a National Natural Science Foundation of China Major Project. We propose to develop computational methodology starting from the theory of electronic excitation processes to predicting the opto-electronic property for organic materials, in close collaborations with experiments. Through developing methods for the electron dynamics, considering superexchange electronic couplings, spin-orbit coupling elements between excited states, electron-phonon relaxation, intermolecular Coulomb and exchange terms we combine the statistical physics approaches including dynamic Monte Carlo, Boltzmann transport equation and Boltzmann statistics to predict the macroscopic properties of opto-electronic materials such as light-emitting efficiency, charge mobility, and exciton diffusion length. Experimental synthesis and characterization of D-A type ambipolar transport material as well as novel carbon based material will provide a test ground for the verification of theory.     

有机光伏材料与器件研究的新进展

近几年有机光伏电池应用研究发展迅猛。本文综述了有机光伏薄膜电池在材料(包括有机小分子材料与聚合物材料)、器件构造方面的最新进展，分析了有机聚合物光伏电池目前效率低的主要原因，并探讨了该领域进一步研究的方向和前景。     

Hierarchical cooperative binary ionic porphyrin nanocomposites

Cooperative binary ionic (CBI) solids comprise a versatile new class of opto-electronic and catalytic materials consisting of ionically self-assembled pairs of organic anions and cations. Herein, we report CBI nanocomposites formed by growing nanoparticles of one type of porphyrin CBI solid onto a second porphyrin CBI substructure with complementary functionality.     

Basic materials physics of transparent conducting oxides

Materials displaying the remarkable combination of high electrical conductivity and optical transparency already from the basis of many important technological applications, including flat panel displays, solar energy capture and other opto-electronic devices. Here we present the basic materials physics of these important materials centred on the nature of the doping process to generate n-type conductivity in transparent conducting oxides, the associated transition to the metallic (conducting) state and the detailed properties of the degenerate itinerant electron gas. The aim is to fully understand the origins of the basic performance limits of known materials and to set the scene for new or improved materials which will breach those limits for new-generation transparent conducting materials, either oxides, or beyond oxides.     

Organic photoresponse materials and devices

Organic photoresponse materials and devices are critically important to organic optoelectronics and energy crises. The activities of photoresponse in organic materials can be summarized in three effects, photoconductive, photovoltaic and optical memory effects. Correspondingly, devices based on the three effects can be divided into (i) photoconductive devices such as photodetectors, photoreceptors, photoswitches and phototransistors, (ii) photovoltaic devices such as organic solar cells, and (iii) optical data storage devices. It is expected that this systematic analysis of photoresponse materials and devices could be a guide for the better understanding of structure-property relationships of organic materials and provide key clues for the fabrication of high performance organic optoelectronic devices, the integration of them in circuits and the application of them in renewable green energy strategies (critical review, 452 references).