Efficient Top-Emitting Polymer Light-Emitting Diodes Using Chromium as Anode

We demonstrate a high eftlciency top-emitting polymer light-emitting diode （TPLED） with chromium （Cr） taking as the anode. The TPLED structure is Cr/poly-3, 4-ethylenedioxythiophene （PEDOT：PSS）/poly [2-（4-3＇,7＇- dimethyloctyloxy）-phenyl]-p-phenylenevinylene） （P-PP V） /Ba/Ag. The Cr （ 100 nm） anode is prepared by sputterdepositing in a vacuum chamber. It is found that the device emissive properties are affected dramatically by the thickness of both PEDOT：PSS and the Ag cathode. Optimized thicknesses of PEDOT：PSS and Ag layer are 60nm and 15nm, respectively. The diode exhibits excellent electroluminescence （EL） properties, such as a turn-on voltage of 3.32 V, luminous eftlciency of 4.41 cd/A and luminance of 6989cd/m^2 at driving voltage of about 9 V.     

Ta2O5的氢热处理对有机薄膜晶体管性能的影响

以高分子聚(2-甲氧基-5-(2-乙基-已氧基)-1,4-苯撑乙烯撑)(MEH-PPV)为半导体有源层、Ta2O5为绝缘层,制备了有机薄膜晶体管(OTFT),研究了氢热处理Ta2O5绝缘层对OTFT性能的影响,并对该器件性能改善的原因进行了分析.结果表明,经氢热处理的Ta2O5绝缘层使MEH-PPV的场效应迁移率提高了一个数量级,从1.24×10-5cm2/(V.s)提高到2.15×10-4cm2/(V.s),阈值电压有所降低.     

导电高聚物的EXAFS研究(Ⅱ)FeCl3掺杂的聚噻吩

Fe K absorption spectra of an electrically conductive polymer——FeCl_3-doped polythiophene and model compound [N(C_2H_5)_4][FeCl_4] were measured with a laboratory EXAFS system, which utilizes a high power rotating-anode X-ray generator (Rigaku model RU-1000) as a X-ray source. The analysis of observed EXAFS data shows that Fe atom is surrounded by four Cl atoms with Fe-Cl distance of 2.19. It is concluded that the dopant exists mainly in the form of FeCl_4~-. The result provides a direct structural information that strongly supports the proposition: the doping process is as follows2FeCl_3+e~-→FeCl_4~-+FeCl_2     

三聚噻吩TCNQ复合物晶体结构的测定-MM与图形技术在测定晶体结构中的应用

本文利用直接法和应用分子力学与图形技术结合的尝试法,测定了取向无序的三聚噻吩TCNQ复合物的晶体结构,采用0PEC程序对复合物晶体进行堆积分析和堆积能的计算。     

乙炔在钒催化体系下的聚合

本工作采用三乙酰基丙酮钒及二乙酰基氧钒同烷基铝组成的催化体系,研究了乙炔聚合的规律及聚乙炔成膜的条件,并初步研究了聚乙炔膜的链节结构、形态结构及室温电导率。     

Unexpected Strong Luminescence of Polysiloxanes Containing Carbazolyl and C60 Moeities as Side Chains

Two types of polysiloxanes,which contain both C60 moieties and carbazolyl groups in the side chains with a difference in the numbers of the reacting site on C60 molecules,were synthesized and their fluorescent properties were studied to distinguish the role of C60 in the luminescent polymers.Our results demonstrated that when C60 moieties are bonded to the polymers as multisubstituents but not linked to the luminescent moieties directly,the luminescence of the resultant polymers were still very strong instead of quenching,even the substituted degree is only 1.01.     

Novel Efficient Light-Emitting Polyfluorene Derivatives Modified by Electron-Deficient Moieties with Nonlinear Structure

Two novel fluorene-based copolymers (PFSD and PFMD) containing squaric acid or maleimide unit in the main chain were synthesized in good yields by Suzuki coupling reaction. The resulting polymers possess excellent thermal stability, high electron affinity and high photolurninescence (PL) quantum yields. They can fluoresce in yellow-light range due to either the charge transfer between a fluorene segment and an electron-deficient containing squaric acid/maleimide segment of the polymers or the Forrster energy transfer between different polymer chains.The results from PL measurements of the isothermally heated polymer thin films show that the commonly observed aggregate excimer formation in polyfluorenes is very effectively suppressed in these two polymers due to the nonlinear structures of maleimide and squaric acid moieties. Double-layer polymer light-emitting diodes (PLED) were fabricated using the resulting polymers as the emitting layers and Ba or Mg：Ag(V：V=10：1) as cathodes.All the devices show bright yellow emission (562-579nm) with different maximum external quantum efficiencies (0.006%-1.13%). Compared with the other devices, indium-tin oxide (ITO)/polyethylenedioxythiophene (PEDOT):polystyrene sulfonic acid (PSS)/PFMD/Mg:Ag has the higher maximum external quantum efficiency of 1.13% at 564cd/m^2 with a bias of 8.4V.     

一类近红外电致发光芴基共聚物的合成和性能研究

基于9,9-二辛基芴与窄带隙单体5,7-二(2-噻吩基)噻[3,4-b]并[1,4]二嗪(DTP),通过Suzuki偶合反应,合成了一系列无规窄带隙的芴基共聚物(PFO-DTP),并对它们的紫外-可见吸收光谱、光致发光和电致发光性能进行了初步研究.共聚物在380 nm和632 nm处有两个明显的吸收峰,其中632 nm处的吸收随着共聚物中窄带隙单体(DTP)含量的增加而加强,最大电致发光峰随着共聚物中窄带隙单体(DTP)含量的增加,从752nm红移到了781 nm.同时与其同分异构体4,7-二(2-噻吩基)苯并噻二唑(DBT)与芴的共聚物PFO-DBT相比,该类聚合物的吸收红移,与近地太阳光谱更为匹配.     

新型含咔唑聚芴类共轭聚电解质及其前驱体的合成与光电性能

采用Suzuki偶合反应成功地合成了一系列在主链上具有不同含量苯并噻二唑单元的聚咔唑和含胺基芴的衍生物:聚[3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并噻二唑-9,9-双(N,N-二甲基胺丙基)芴](PCzN-BTDZ);通过对所得聚合物的季铵盐化后处理得到了其相应的聚电解质衍生物:聚[3,6-(N-(2-乙基己基))咔唑-2,1,3-苯并噻二唑-9,9-(双(3′-(N,N-二甲基)-N-乙基铵)丙基)芴]二溴(PCzNBr-BTDZ)。通过对它们的电致发光性能的研究,发现所有的聚合物用高功函数铝作阴极的器件具有和用钡/铝作阴极的器件相近的发光性能,说明这类聚合物具有良好的电子注入性能。不同比例的2,1,3-苯并噻二唑(BTDZ)的引入使聚合物中发生有效的能量转移,调节了聚合物的发光颜色;同时也提高了聚合物的器件性能。其中聚合物PCzN-BTDZ1在器件结构为ITO/PEDOT/PVK/Polymer/BaAl时的效率达0.99%,高于PCzN在相同器件结构时的效率(0.14%)。     

含有烷基侧链的杂环芴基共聚物的光电性能

通过对9,9-二辛基芴(DOF)与4,7-二噻吩-2,1,3-萘并噻二唑(DNT)共聚物(PFDNT)和9,9-二辛基芴(DOF)与4,7-二(3-己基噻吩)-2,1,3-萘并噻二唑(HDNT)共聚物(PFHDNT)的光电特性进行比较研究,发现烷基侧链上引入杂环窄带隙单体能有效提高芴基共聚物的分子量和光荧光的量子产率。共聚物PFHDNT的光致发光和电致发光峰相对于共聚物PFDNT发生了蓝移,可能是由于长烷基侧链的空间位阻减小了π^*有效共轭长度导致其发射峰发生蓝移。此外共聚物PFHDNT器件的电荧光量子效率并未由于引入烷基侧链而降低。