有机功能材料及有机晶体结构的研究

【作者】 吕银祥；

【导师】 卜海山； 徐伟；

【作者基本信息】 复旦大学 ， 材料物理与化学， 2004， 博士

【摘要】 本文主要由两部分构成：（1）有机功能材料的制备及性质，包括有机发光材料，有机电双稳材料以及有机电整流材料；（2）有机晶体的结构研究。 在有机发光材料方面，由于现有的性能较好的发光材料，其专利大都掌握在国外大公司手中，国内具有自主知识产权的高性能材料很少，本文的工作主要集中在新材料的开发方面，在前人的基础上有所创新．合成了一系列金属有机络合物，噁二唑及喹啉衍生物等有机电致发光材料；合成了芳胺类空穴传输材料H40，H41等；合成了多分支星状杂环类分子材料TPM，TIM等。制作了发红、绿、黄光的器件，其中器件ITO／H40／Alq₃／LiF／Al的最大发光亮度为10300cd／m²，当工作电压为9V，电流密度为150 mA／cm²，发光亮度为1000 cd／m²时有最大发光效率为1.8cd／A。器件ITO／H40／Alq₃／Mg：Ag在6V的驱动电压下，在未采取任何封装情况下，从150cd／m²（20mA）的亮度衰减到50cd／m²（180mA）的时间可达60分钟。 制备了一种喹啉类多芳基取代材料ADTQ，作为有机电致发光器件的发光材料及掺杂材料，并发现一种新型的一步关环反应。 在单有机电双稳材料方面，现有的许多有机材料熔点较低，热稳定性比较差，不适宜在室温下工作，还有一些有机材料的成膜性能较差，不适合在真空中制备薄膜器件；此外，绝大多数有机电双稳材料写入后都不可擦除，尤其不可以用电擦除，这就使得有机电双稳材料的应用受到了很大的限制。因此，本文在探索寻找高效率、高稳定性并且可擦写的新型单有机电双稳材料方面进行了一系列的努力，取得的一些进展。本文发现了三种具有电双稳性质的单有机分子材料BN4、ONCN及DBCN，制备了一系列类似材料。BN4制成的电双稳器件Ag／BN4／Al具有很好的电双稳特性，跃迁前后的阻抗比达到10⁵，最多能够进行2000次擦写，这种可用电信号擦写的性质可用来制备可擦写的存储器，逻辑门以及过电压保护器。 在有机整流材料方面，设计并合成了一类D-π-A型具有整流特性的有机材料MR-X，制成的整流器件Cu／MR-X／Cu的整流比可达100以上，Cu／MR-1／Ag的整流比可达10⁴；基于MR-X整流分子的结构，引入巯基，设计并合成了整流分子材料PPSC，使之与金膜自组装形成高度有序的整流分子膜，得到了整流比为1.89的器件Au／PPSC／Au，分析了器件的缺陷。 本文发现，原本高度对称的星状分子，在晶体结构中，分子对称性破坏或降低，表现为手性分子；以四（4-氰基苯氧基甲基）甲烷为例，从分子间氢键作用的角度，解释了该现象形成的原因。为了验证该现象的普遍性，设计并合成了一系列的对称结构的分子材料，将其培养成单晶，用于研究不对称性的形成。穿旦丈学浮全学夕居戈摘要 本文制备了1 00多种化合物，其中多数分子具有特殊的功能性质，发光材料的性能处于国内领先水平，电双稳材料及整流材料处于国际同类水平;此外，还发现了对称分子在晶体结构中自发形成手性分子的现象.更多还原

【Abstract】 This thesis is composed of two parts: (1) Preparation and properties of organic functional materials including electroluminescence materials, electrical bistable materials and rectification materials. (2) Study of organic crystal structure.Since the electroluminescence materials based on our national patents are very scarce, our main work is focused on the development of new materials. Several materials was synthesized, such as electron transport and host emitting materials: organometallics, oxadiazole and quinoline derivatives; hole-transport materials: aromatic amines H40, H41; and star-shaped molecule materials TPM, TIM etc. Some organic lighting-emitting diodes were prepared, which emit red, green and yellow light. The device of ITO/H40/Alq3/LiF/Al reached a luminance efficiency of 1.8cd/A at a drive voltage around 9V, current density of 150 mA/cm2 and a luminance of 1000 cd/m2, and a maximum luminance of 10300cd/m2 at a drive voltage of 14V. At the current density of 20 mA/cm2, and an initial luminance of 150cd/m2, the device of ITO/H40/Alq3/Mg:Ag showed extrapolated life of over one hour without any seal at room temperature.A series of novel quinoline derivatives with polyaromatic system and special Donor-Acceptor structure, are obtained. They show high melt points and thermal stability, and promise themselves as a type of good molecular materials, e.g. in the field of organic light-emitting-diodes (OLEDs). An extraordinary phenomena is described in the normal condensation of arylaldehydes with arylethylidenemalono-nitriles, which had never reported; and the results indicate that another important reaction process, ring closure reaction, can operate in this traditional reaction.The existing organic electrical bistable materials showed some shortcomings, such as low melt point, poor thermal stability, unsuitability for working in room temperature, tend to be crystal, etc. Most of the films based on these materials can’t be erased, especially electrical erased, after been written. Our efforts are concentrated on finding high efficient, good stability and electrical writing-erasing materials. A series of organic electrical bistable materials, such as BN4> ONCN and DBCN, was designed and synthesized. The device of Ag/BN4/Al had interesting electrical property, it appears high resistance (37M) under high voltage (>5V) and low resistance ( 102 ) under low voltage (<3V), the rate of resistance reach 105. In the best result, the device can write-read more than 2000 times, so it can be used for ultrahigh-density storage.Organic materials of D- - A type, such as MR-X, PPSC, was designed and synthesized. The molecular devices base on MR-X have good electrical rectification, such as Cu/MR-X/Cu has a ratio of the rectification of over 100, and Cu/MR-1/Ag can reach 10000. Analogous to the structure of MR-X, the molecular materials of PPSC, with a special thiol group, was designed and synthesized. A device of Au/ PPSC/Au, with signal layer of ordered rectification molecular by the self-assembled effect of thiol and the Au film, was prepared. A ratio of the rectification of 1.87 was obtained. Though the result was not so good, a general understanding of the problems lying in the manufacture process of the device was gotten.We found the symmetry was destroyed or decreased in the crystal structure of symmetrical star-shaped molecules, such as tetra((4-cyanophenoxy)methyl)-methane, tetra(N-pyrrolemethyl)methane, and a center of charility was self-formed. The phenomena was discussed by analyzing the intermolecular hydrogen-bonding interactions of tetra((4-cyanophenoxy)methyl)-methane. What’s more, we also found that di(4-phenylpiperazin-l-yl)methane has Z’ = 4 structure without obvious pseudosymmetry. The structure contains a center carbon, which was different from most of the molecules with Z’ >1.In summary, above 100 compounds have been prepared, most of which has special functions. The results based on these organic materials had reached advanced level in our reach field. Furthermore, we found that, charility c更多还原