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101.
Ping Wang Dr. Teng‐Feng Xie Prof. Hai‐Yan Li Dr. Liang Peng Dr. Yu Zhang Dr. Tong‐Shun Wu Dr. Shan Pang Dr. Yun‐Feng Zhao Dr. De‐Jun Wang Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4366-4372
Functional spheres : Monodisperse gold‐doped titania spheres with tunable sizes under high concentration of titanium precursor have been synthesized by introducing trace amounts of chloroauric acid into the reaction system. Surface photovoltage, surface photocurrent, and transient photovoltage measurements (see figure) of annealed samples reveal that gold nanodots can act as both electron acceptors and donors under the illumination of different wavelengths of light.
102.
The emission of composite conjugated polymer (MEH‐PPV)/fullerene (PCBM) nanoparticles is investigated by single particle spectroscopy (SPS), and changes in vibronic structure with nanoparticle composition are evaluated by means of a detailed Franck–Condon analysis. Consistent with previous reports we find that the emission spectra can be modeled as the superposition of two types of emitters, one with aggregate character and one with molecular character. Major findings from the fitting of the SPS data to a Franck–Condon model are that 1) the occurrence of each of the two types of emitters changes with nanoparticle composition to the point that no aggregate emitters are detected (at 50 wt % PCBM), 2) at the highest PCBM doping levels (75 wt % PCBM) aggregate emitters reappear due to nanoscale phase separation in the composite nanoparticles, 3) the molecular emitters show small Huang–Rhys factors that increase with PCBM doping, indicative of extensive delocalization and exciton migration that is reduced by the disorder introduced in the polymer material by PCBM doping and 4) the aggregate emitters show large Huang–Rhys factors, indicative of the localized nature of these energy trap sites, with a broad distribution of values of these Huang–Rhys factors. The latter observation suggests a broad heterogeneous distribution of aggregate morphologies in blended conducting polymer materials, which can be attributed to variations in polymer chain folding and stacking at the aggregate sites. The reported results obtained by the SPS approach show how blending conjugated polymers with fullerenes at various doping levels induces changes in interchain interactions and aggregate site density even at length scales below a few tens of nanometers that affect conjugated polymer material properties, an observation that has gone unnoticed in bulk studies of blended conjugated polymer films. 相似文献
103.
David Gendron Pierre‐Olivier Morin Ahmed Najari Mario Leclerc 《Macromolecular rapid communications》2010,31(12):1090-1094
New aromatic compounds with a pyridazine core have been synthesized. Four electron‐withdrawing monomers have been easily prepared from simple condensation reactions and ring closure procedures. Optimized HOMO, LUMO, and bandgap energy levels have been obtained. The resulting conjugated polymers have been tested in organic solar cells. First studies have revealed power conversion efficiencies up to 0.5% for an active area of 1.0 cm2.
104.
理论研究了有ITO(indium tin oxide)透明导电膜的多层平面分层介质系统的电磁性能,给出的理论曲线和实测曲线符合很好.多层平面分层介质系统的电磁性能与ITO膜(方块电阻为8Ω)所在界面位置和平面分层介质系统层数及各层厚度等有关.优化设计了一种含有ITO透明导电膜的厚度仅7.35mm的四层平面分层介质系统,其在8—18GHz频段内电磁波反射性能很好.作为多层平面分层系统中的ITO导电膜,其方块电阻应低于30Ω,并且越小,其反射性能越好.
关键词:
多层平面介质系统
电磁性能
ITO透明导电膜 相似文献
105.
三苯胺类自供能电致变色材料合成及器件开发 总被引:1,自引:0,他引:1
设计并合成了一种新型三苯胺衍生物: (4-((4-(二甲基氨基)苯基)(苯基)氨基)苄基)膦酸, 并研究了它的光谱电化学性质和光伏性质. 光谱电化学谱图表明该化合物具有电致变色性能: 通过施加不同电压, 该化合物薄膜可以在透明态和着色态之间转换, 且在629 nm处透过率对比度达到最大, 为64.2%. 由该材料组装成的自供能电致变色器件具有光伏性能, 光电转化效率可以达到0.32%. 和传统的光电变色器件相比, 该新型器件具有结构简单、制备成本低廉、绿色环保等特点, 预计在建筑、汽车、显示器等领域将有广泛的应用. 相似文献
106.
Novel organic and inorganic hybrid photovoltaic devices were thbricated by in-situ electrochemical copolymerization of 3-methylthiophene(3MT) and bithiophene(BT) into the pores of nanostructured TiO2 sintered on fluorine-doped tin oxide(FTO) substrate. The photoactive layer was investigated by Fourier transform infrared(FTIR) spectroscopy, ultraviolet-visable(UV-Vis) spectrometer, scanning electron microscope(SEM) and cyclic voltammo- gram characterization. Device efficiency based on different molar feed ratios of 3MT and BT during electrochemical polymerization, and the effect of in-situ copolymer state(doped by electrolyte and de-doped) were measured and compared. Under the solar illumination of 100 mW/cm2(AM 1.5), an optimized device efficiency of 0.938% was obtained when the molar ratio of 3MT to BT was 500:1, polymerization time was 500 s and the system was in doped copolymer state, respectively. The mechanism of overall photovoltaic parameter improvement was discussed. 相似文献
107.
108.
通过原位聚合方法制备不同配比的聚吡咯/氧化石墨(PPy/GO)复合物,将其用NaBH4还原得到聚吡咯/还原氧化石墨烯(PPy/RGO)复合物,采用X射线衍射、红外光谱和场发射扫描电子显微镜(FESEM)对其结构和形貌进行物理表征。 采用循环伏安、恒电流充放电和交流阻抗等电化学方法系统研究了所制备样品的电化学性能。 实验结果表明,在电流密度为0.5 A/g、吡咯(Py)与GO质量比为95∶5时,得到的复合物还原前后比电容分别可达401.5和314.5 F/g,远高于单纯的GO(34.8 F/g)和PPy(267.5 F/g)。 经过1200圈循环稳定性测试后,PPy/RGO复合物比电容保持了原来的62.5%,与PPy和PPy/GO(电容保持率分别为16.8%和46.4%)相比,PPy/RGO表现出更好的循环稳定性能,有望成为超级电容器电极材料。 相似文献
109.
研究了一种新型的有机/无机杂化钙钛矿材料(3-BrC3H6NH3)2CuBr4薄膜的聚集态形貌和良好的微观有序性特征, 霍尔迁移率测试结果表明该材料为p型半导体, 空穴迁移率为0.0025 cm2•V-1•s-1. 利用其在紫外-可见光谱范围内与C60薄膜具有良好的光吸收互补性, 制备并研究了(3-BrC3H6NH3)2CuBr4/C60层状异质结结构中的暗态传输和光伏性能. 对不同退火温度下杂化钙钛矿薄膜的聚集态特性和器件性能之间的联系进行了探讨, 结果表明在低温退火条件下, 由于钙钛矿结构材料中有机组分排列更加有序, 器件显示更好的性能. 相似文献
110.
Xiaoying Zheng Jin Chen Jinhui Peng C. Srinivasakannan Rongsheng Ruan 《Phase Transitions》2018,91(3):308-315
In this work, we demonstrate a novel synthesis of synthetic rutile from high titanium slag. This rutile TiO2 was obtained by a simple one-step microwave roasting route. The influence of microwave roasting temperature and duration on the phase transformation of high titanium slag has been assessed. X-ray diffraction (XRD) results indicate that the intensity of anosovite (Fe3Ti3O10) phase, which were the major phase of high titanium slag of carbon thermal reduction of ilmenite ores, decreased rapidly while the peaks for rutile TiO2 phase increased with increase in the microwave roasting temperature. The scanning electron microscope (SEM) images revealed formation and the particle-size distribution of rutile TiO2 phase. Based on XRD and SEM analysis, confirmed the dependence of phase structure, composition and crystallite size on the process conditions of microwave roasting. 相似文献