修饰LB膜法制备聚3,4-乙烯二氧噻吩薄膜的光电性能

采用修饰LB膜法以二十烷酸(AA)LB膜为模板,通过3,4-乙烯二氧噻吩(EDOT)单体在LB膜亲水基团间聚合,制备了AA/PEDOT复合LB膜。UV-Vis、FT-IR和XPS分析表明EDOT在多层膜中有效聚合,生成了PEDOT导电聚合物;XRR和SIMS分析表明薄膜具有较好的层状有序结构,进一步研究发现EDOT在AA多层膜中的聚合破坏了原有LB膜的有序性,这可能与聚合过程对层状结构产生的破坏作用有关;采用四探针仪及半导体测试仪研究了薄膜导电性能,发现AA/PEDOT多层膜的电导率随处理时间的变化产生突变,这与多层膜中导电通道的"渝渗"有关,在有效导电网络连通后电导率发生了突变。测试结果还表明AA/PEDOT膜导电性明显优于PEDOT旋涂膜和ODA-SA/PEDOT-PSS复合膜,这是由于原位制备的PEDOT共轭度较高,且薄膜具有很好的层状有序结构。     

导电聚合物有序超薄膜结构及光电特性

采用LB 膜诱导沉积法制备聚(3, 4)乙烯二氧噻吩(PEDOT)高度有序导电聚合物薄膜.实验表明,聚(3, 4)乙烯二氧噻吩-聚苯乙烯磺(PEDOT-PSS)纳米粒子对单分子层具有包裹作用,形成了稳定的复合单分子膜;二次离子质谱(SIMS)和小角X 射线反射(XRR)分析表明十八胺-硬脂酸/聚(3, 4)乙烯二氧噻吩-聚苯乙烯磺(ODA-SA/PEDOT-PSS)组装体优于十八胺/聚(3, 4)乙烯二氧噻吩-聚苯乙烯磺ODA/PEDOT-PSS,具有更好的成膜性能,表面粗糙度小且稳定可控,薄膜具有较好的有序结构.设计了不同的测试结构,测量了复合膜的垂直电导率和水平电导率,研究了薄膜的直流电流-电压特性,采用变程跳跃模型(VRH)对结果进行了拟合,表明三维变程跳跃模型(3D-VRH)可以较好的解释多层膜中载流子的迁移.     

导电聚合物有序超薄膜成膜性能的研究

采用LB膜诱导沉积法制备PEDOT高度有序导电聚合物薄膜,采用的工艺是将十八胺(ODA)与聚3,4-乙烯二氧噻吩/聚苯乙烯磺酸(PEDOT-PSS)先形成ODA包裹PEDOT-PSS纳米粒子的组装体,然后再将其铺展于气/液界面,制备PEDOT-PSS复合LB膜。实验表明,PEDOT-PSS纳米粒子对单分子层具有包裹作用,形成了稳定的复合单分子膜;不同膜压下制备的膜表面形貌不同,较高膜压下得到颗粒紧密排列的薄膜,亚相温度23℃、PEDOT-PSS浓度1×10-3mol/L、压缩速率5mm/min、拉膜速率为1mm/min的条件下薄膜具有较好的成膜性能。     

PEDOT/聚己内酰胺导电复合纱线的制备和表征

采用化学气相沉积法(CVD)制备聚3,4-乙烯二氧噻吩(PEDOT)/聚己内酰胺导电复合纱线,研究PEDOT/聚己内酰胺导电复合纱线的表面形貌、化学组成及热学性能,并探讨氧化剂质量浓度、浸渍时间及沉积时间对复合纱线导电性能的影响。实验结果表明,聚己内酰胺纱线表面形成PEDOT导电层赋予纱线优良的导电性能,其质量比电阻可低至2.81Ω·g·cm-2;随着氧化剂质量浓度的增加和沉积时间的延长,复合纱线的质量比电阻先降低后增加;浸渍时间越长,复合纱线的质量比电阻越小,导电性越好;复合纱线的热稳定性在温度高于480℃时优于普通聚己内酰胺纱线。     

化学气相沉积导电聚合物复合纳米薄膜及性能

采用化学气相聚合法制备了聚-3,4-乙烯二氧噻吩(PEDOT)/还原氧化石墨烯(RGO)复合薄膜。首先用旋涂法制备氧化剂/氧化石墨烯(GO)薄膜,然后将薄膜置于3,4-乙烯二氧噻吩(EDOT)气相聚合装置中,形成PEDOT/GO复合薄膜。将获得的PEDOT/GO复合薄膜用葡萄糖还原剂进行处理,获得PEDOT/RGO复合薄膜。导电性测试表明,GO被还原后复合薄膜的电导率为35.3S/cm,明显高于PEDOT/GO(14.6S/cm)和纯PEDOT(17.3S/cm)薄膜的电导率。电化学特性研究表明,RGO的加入使得PEDOT/RGO导电聚合物复合纳米材料具有优良的电化学特性及稳定性,薄膜的比电容为176.7F/g。循环测试800次后,比容量保持率为84%,具有良好的电化学稳定性。这种化学气相聚合制备的聚合物复合纳米薄膜在超级电容器及导电材料领域有着很好的应用前景。     

聚3,4-乙撑二氧噻吩薄膜制备的研究进展

聚3,4-乙撑二氧噻吩(PEDOT)薄膜的电导率高、稳定性好、透明性佳,有广阔的应用前景。许多科技工作者致力于PEDOT薄膜的制备研究。简要介绍了导电PEDOT薄膜制备方法的研究进展。常用的制备方法有电化学聚合法,物理涂覆法,物理沉积法,原位聚合法。     

上海硅酸盐所在有机-无机复合热电材料领域取得重要进展

正近日,中国科学院上海硅酸盐研究所陈立东研究员、姚琴副研究员的研究团队在聚3,4-乙烯二氧噻吩(PEDOT)基有机/无机复合热电材料领域取得重要进展。该团队采用新型氧化剂,通过自抑制聚合法,获得了高膜厚无气孔PEDOT∶DBSA-Te量子点复合热电薄膜。研究团队首先通过设计调控导电高分子对阴离子的分子结构来调控对阴离子的位阻,实现了薄膜自抑制法聚合     

导电聚合物有序超薄膜材料特性的分析

首次采用LB膜诱导沉积法制备PEDOT高度有序导电聚合物薄膜,所采用的工艺是将十八胺(ODA)与聚3,4-乙烯二氧噻吩/聚苯乙烯磺酸(PEDOT-PSS)先形成ODA包裹PEDOT-PSS纳米粒子的组装体,然后再将其铺展于气/液界面,制备PEDOT-PSS复合LB膜.研究了复合单分子膜在气/液界面的成膜性能,对不同层数的LB膜进行了较为详细的微观分析和结构表征.采用UV-Vis光谱对不同层数的复合膜进行了表征,发现ODA-SA/PEDOT-PSS膜具有比ODA/PEDOT-PSS膜好得多的成膜性,这是由于生成的氨基酸改善了复合膜的成膜性;FT-IR和XPS分析表明固态复合膜中存在静电作用力,复合膜靠静电力在气/液界面进行组装.实验表明,PEDOT-PSS纳米粒子对单分子层具有包裹作用,形成了稳定的复合单分子膜;在十八胺(ODA)和硬脂酸(SA)摩尔比2:1、亚相温度23℃、PEDOT-PSS浓度1×10-3mol/L、压缩速率5 mm/min、拉膜速率为1 mm/min的条件下薄膜具有较好的成膜性能.     

高电导率聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸复合物的制备及表征

采用聚苯乙烯磺酸作为电荷平衡掺杂剂,通过氧化3,4-乙烯二氧噻吩聚合制备聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸(PEDOT∶PSS)。采用红外光谱、X-射线衍射图谱和四探针电导率测试仪分别对其结构和导电性能进行表征。X-射线衍射图谱表明PEDOT∶PSS为半晶态结构。电导率测试结果表明聚合工艺条件对PEDOT∶PSS电导率均有显著的影响,并在最佳工艺条件下制备出电导率高达73S/cm的PEDOT∶PSS。     

PEDOT-PSS导电聚合物LB薄膜的制备和性能

研究了十八胺(ODA)及其与硬脂酸(SA)混合单分子膜在导电聚合物聚3,4-乙烯二氧噻吩/聚苯乙烯磺酸(PEDOT-PSS)胶体亚相上的成膜行为和复合LB膜在室温下的电学性能.结果表明:ODA-SA/PEDOT-PSS复合LB膜具有更好的成膜性能,表面粗糙度小且稳定可控,薄膜具有较好的有序结构;ODA-SA/PEDOT-PSS膜电导率高于ODA/PEDOT-PSS复合LB膜,其电导率呈各向异性,水平电导率(σ‖)与垂直电导率(σ⊥)之间相差3～4个数量级,Ⅰ-Ⅴ曲线呈指数关系,为典型的电子隧穿类型.     

Simulation of the thin-film thickness distribution for an OLED thermal evaporation process

A design of an OLED (organic light-emitting device) fabrication system strongly depends on a thermal evaporation process. In an OLED evaporation process, the essential requirements include good uniformity of the film thickness over a glass substrate. In this paper, a process simulation model was developed to predict the film thickness distribution by understanding system design parameters that affect the uniformity of film thickness. Based on the method developed in this study, the uniformity of the thickness in an organic layer was successfully controlled. The developed method allowed the manufacture of high quality OLED displays.     

Preparation and characterization of conducting poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) Langmuir-Blodgett film

The self-assembly of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) nanoparticles at an air/water interface was achieved by means of the electrostatic force between an octadecylamine (ODA) monolayer and PEDOT-PSS nanoparticles. A surface pressure (π)-area (A) isotherm and X-ray photoelectron spectroscopy of the composite film were used to confirm the electrostatic force between the SO₃⁻ group of PSS and the NH₄⁺ group of aliphatic amines. Monolayer and multilayer composite films of ODA/PEDOT-PSS and ODA-stearic acid (SA)/PEDOT-PSS were fabricated. These solid Langmuir-Blodgett films were investigated by the UV-Vis spectrum, atomic force microscopy, and X-ray diffraction method. It is observed that ODA-SA/PEDOT-PSS films had a higher film-forming capability than ODA/PEDOT-PSS films and an ordered multilayer structure was developed. The conductive properties of ODA-SA/PEDOT-PSS LB films were investigated in detail. Factors influencing the film conductivity such as the layer number and surface pressure were discussed and the conductive mechanism was also studied.     

Development of inverted OLED with top ITO anode by plasma damage-free sputtering

A newly-developed damage-free sputtering system, Hyper-thermal Neutral Beam (HNB) sputtering, was evaluated for the production of organic light emitting diode (OLED) devices. An indium tin oxide (ITO) pixel layer as an anode electrode was deposited directly on the Hole Transport Layer (HIL) of an Inverted Bottom emission OLED (IBOLED) structure. Two types of IBOLED devices were fabricated to assess the level of process damage by the HNB sputtering deposition process. The characteristics of the leakage current at reverse bias and the UV exposure test confirmed that HNB ITO sputtering does not damage the underlying organic layers in the IBOLED device with the top ITO anode deposited by HNB sputtering, which is in comparison with a normal IBOLED with a top Au anode deposited by conventional thermal evaporation. However, the IBOLED device using HNB sputtering process showed some degradation of the turn-on characteristics and current efficiency. This degradation was not induced by damage from the HNB sputtering process but was generated by the permeation of Fe impurities from the stainless steel chamber and the low conductivity of HNB sputtered ITO thin film.     

Work function and valence band structure of tin-doped indium oxide thin films for OLEDs

Transparent conducting ITO thin film has been widely used as anode material in OLEDs due to its good optical transparency, low electrical resistivity, ease of patterning, high work function and efficient hole injection properties. The interface between ITO and organic layer in OLED device is thus important and can influence the electrical and luminescent properties. In this report, ITO substrates were treated with 20% H₃PO₄ solution. The corresponding changes in crystalline morphology were studied by X-ray diffraction. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) were performed at ∼10⁻⁹ Torr to study the work function and the valence band structure of ITO substrates. It was found that work function became slightly lower after the treatment, probably caused by the formation of metal complex compounds and metal hydroxides. The binding energy of In 3d_5/2 shifted from 444.6 to 445.3 eV. This shifting was referred to the formation of In-OH bonding. It would be easier to provide electron by In-OH bonding than by In-O-In or Sn-O-Sn when photons reached ITO surface. The interface between ITO and CuPc was improved through polar surface and less aggregation. In addition, the OLED devices exhibited improved performance in both external quantum efficiency and luminescence efficiency.     

(PEDOT-PSS)-碳纳米管复合膜硅基太阳能电池

碳纳米管-Si(CNTs-Si)肖特基太阳能电池具有制作简单、成本低的优势。然而,受限于CNTs薄膜的电阻高、结区均匀性差、反光严重等因素,该类器件的光电转换效率仍较低。本文研究了聚3,4-乙撑二氧噻吩-聚苯乙烯磺酸盐(PEDOT-PSS)-CNTs复合透明膜的制备及其在硅太阳能电池中的应用。电流-电压曲线表明,PEDOT-PSS的引入可以大幅度提升CNTs-Si器件的光电转换效率(从5.9%到11.6%)。作为透明电极,复合膜中的取向CNTs可有效地收集和传导太阳能电池结区的光生空穴,而PEDOT-PSS则有效填补了CNTs膜的面内空隙,进而增加了肖特基结的面积。采用表面刻有倒金字塔结构的聚二甲基硅氧烷(PDMS)作为减反层,有效地降低入射光的反射,增加Si表面对光的吸收,进一步将(PEDOT-PSS)-CNTs-Si器件的光电转换效率提升至12.4%。电子束感生电流技术表明器件的光电转换主要基于复合膜与Si之间的肖特基结。     

Amorphous indium tin oxide electrodes for piezoelectric and light-emitting device deposited by vacuum roll to roll process

The amorphous indium tin oxides (ITOs) and the transparent conducting oxides (TCOs) electrode on the flexible polymer substrate, polyvinylidene difluoride (PVDF), and their application to the suggested combinational device system were studied. The lower range ordered crystalline structure of the ITOs enable the reduction of micro-cracks or defect grains under flexible conditions. With the piezoelectric function of substrate polymer, which is added to the display function with OLED (Organic light emitting diodes), the pattern design with the separated electrodes for two devices for emitting light and vibration was considered. From these results, the concept of a combinational flexible electronic device system with a functional polymer substrate could be suggested.     

Organic light-emitting diode with polyaniline-poly(styrene sulfonate) as a hole injection layer

In order to improve the performance of organic light emitting diodes (OLED), a water-dispersed polyaniline-poly(styrene sulfonate) (PANI-PSS) was used as a hole injection layer (HIL). The current-voltage and luminescence-current characteristics of the OLED devices were investigated as functions of PANI:PSS weight ratio and the kind of dopants. The PANI-PSS film coated on the indium-tin oxide showed a reduced surface roughness, higher work function, and improved transparency, compared to poly(3,4-ethylenedioxythiophene) (PEDOT)-PSS. In addition, PANI-PSS HIL led to a better operation voltage reduction (ca. 15%) and displayed a higher level of luminance performance (ca. 30%) than the commercial PEDOT-PSS system.     

Cesium-incorporated indium-tin-oxide films for use as a cathode with low work function for a transparent organic light-emitting device

Transparent organic light-emitting devices (TOLEDs) were successfully fabricated utilizing a novel transparent conducting cathode with low work function. Cesium-incorporated indium-tin-oxide film was deposited on the organic layers with negligible damage by simultaneous operation of RF magnetron sputtering using an ITO target and vacuum evaporation of metallic cesium. Incorporation of cesium in the ITO film was confirmed by XPS analysis. The work function (4.3 eV) determined by photoelectron spectroscopy in air (PESA) was lower than that of 0.3-0.4-eV without cesium-incorporation and stable under the atmospheric environment. The electron injection efficiency of cesium-incorporated ITO cathode in the present transparent OLED fabricated was comparable to that of the previous double-layered structure comprising of ITO cathode and an organic buffer layer (BCP) doped by evaporation of cesium [T. Uchida, S. Kaneta, M. Ichihara, M. Ohtsuka, T. Otomo, D.R. Marx, Jpn. J. Appl. Phys., 44, No. 9 (2005) L282].     

Improving efficiency of organic light-emitting diodes fabricated utilizing AZO/Ag/AZO multilayer electrode

Multilayer transparent electrode based on Al-doped zinc oxide (AZO)/Ag/Al-doped zinc oxide (AZO) was fabricated by sputtering, and a green organic light-emitting diode (OLED) device utilizing AZO/Ag/AZO as anode was fabricated. The AZO/Ag/AZO multilayer film exhibited superior square resistance and optical transmittance to those of commercial indium tin oxide (ITO). In comparison with the green OLEDs based on ITO and pure AZO anode, the green OLED based on AZO/Ag/AZO showed the highest light-emitting efficiency. The results indicate that AZO/Ag/AZO multilayer electrodes are a promising low-cost, low-toxic and low-temperature processing electrode scheme for OLED application.     

Liq的合成和提纯及蓝色OLED的试制

报导了8-羟基喹啉锂（Liq）的合成及其提纯方法；用元素分析、X射线衍射谱、紫外吸收光谱对提纯后的样品性能进行表征；研制了结构为ITO／PVK：TPD／Liq／Al的蓝色发光器件，用原子力显微镜分析了纯度与Liq薄膜的表面形态及器件发光性能间的关系，并且也研究了其光致发光和电致发光特性。