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排序方式: 共有96条查询结果,搜索用时 15 毫秒
1.
This article reviews the recent development of organic electron transport materials applied in the fields of organic photoconductors, light-emitting diodes, field-effect transistors and solar cells. Several technologies for charge carrier mobility measurement are summarized and compared, and a series of basic principles for designing high-performance organic electron transport materials are suggested as well. 相似文献
2.
Quanxiang Yan Lijian Zuo Zhuowei Gu Ligong Yang Rong Wang Mang Wang Hongzheng Chen 《中国化学》2013,(11):1380-1384
We have studied the effect of silicon nanocrystals (SiNCs) as a third component on performance of organic bulk heterojunction solar cells composed of poly[2-methoxy,5-(2'-ethylhexyloxy)-l,4-phenylene vinylene] (MEH- PPV):[6,6]-phenyI-C61-butyric acid methyl ester (PCBM) blend film. By adding suitable amounts of SiNCs into MEH-PPV:PCBM blend, the device performance such as external quantum efficiency, short circuit current density (Js(), and power conversion efficiency (PCE) improved. Incorporation of 2.5% SiNCs in the blend led to 13.6% improvement of Jsc, which in turn resulted in 18% improvement of PCE up to 2.28%. The improved performance was mainly due to the improvements both in the charge generation from the interface of MEH-PPV/SiNCs and the charge collection at the cathode. 相似文献
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采用松理化学气相沉积(即PCVD)技术,在不同的温度和时间下制备2组TiN涂层试样;讨论了温度与时间对涂层性能的影响,并在微观结构分析基础上,讨论了时间和温度等工艺参数与微观结构和性能间的关系 相似文献
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Chairungsi N Jumpatong K Phutdhawong W Buddhasukh D 《Molecules (Basel, Switzerland)》2006,11(5):309-317
Electrocoagulation of a plant extract and certain substances representative of selected classes of plant pigments, viz. chlorophyll, a carotenoid, a phenolic substance and a tannin, was performed in ethanol containing varying amounts of water (15-75%). The results showed that the extent and efficiency of coagulation of these substances tends to vary in a manner directly related to the water content of the solvent, although the tannin and the phenolic substance were less sensitive to the solvent composition and are equally well coagulated in all solvent systems studied. The findings can be applied to the removal of these substances from aqueous alcoholic plant extracts using the electrocoagulation technique. 相似文献
7.
Zhongqiang ZHANG Shuhua ZHANG Zhixi LIU Zhiguo ZHANG Yongfang LI Changzhi LI Hongzheng CHEN 《物理化学学报》2019,35(4):394-400
Non-fullerene electron acceptors have attracted enormous attention of the research community owing to their advantages of optoelectronic and chemical tunabilities for promoting high-performance polymer solar cells (PSCs). Among them, fused-ring electron acceptors (FREAs) are the most popular ones with the good structural planarity and rigidity, which successfully boost the power conversion efficiencies (PCEs) of PSCs to over 14%. In considering the cost-control of future scale-up applications, it is also worthwhile to explore novel structures that are easy to synthesize and still maintain the advantages of FREAs. In this work, we design and synthesize a new electron acceptor with an unfused backbone, 5, 5'-((2, 5-bis((2-hexyldecyl)oxy)-1, 4-phenylene)bis(thiophene-2-yl))bis(methanylylidene)) bis(3-oxo-2, 3-dihydro-1H-indene-2, 1-diylidene))dimal-ononitrile (ICTP), which contains two thiophenes and one alkoxy benzene as the core and 2-(3-oxo-2, 3-dihydroinden-1-ylidene) malononitrile (IC) as the terminal groups. The synthetic route to ICTP involves only three steps, with high yields. Density functional theory calculations indicate that the non-covalent interactions, O…H and O…S, help reinforce the space conformation between the central core and the terminals. ICTP shows broad and strong absorption in the long-wavelength range between 500 and 760 nm. The highest occupied molecular orbital and lowest unoccupied molecular orbital levels of ICTP were measured to be -5.56 and -3.84 eV by cyclic voltammetry. The suitable absorption and energy levels make ICTP a good acceptor candidate for medium bandgap polymer donors. The best devices based on PBDB-T:ICTP showed a PCE of 4.43%, with an open circuit voltage (VOC) of 0.97 V, a short circuit current density (JSC) of 8.29 mA∙cm-2, and a fill factor (FF) of 0.55, after adding 1% 1, 8-diiodooctane (DIO) as the solvent additive. Atomic force microscopy revealed that DIO could ameliorate the strong aggregation in the blended film and lead to a smoother film surface. The hole and electron mobilities of the optimized device were measured to be 9.64 and 2.03 × 10-5 cm2∙V-1∙s-1, respectively, by the space-charge-limited current method. The relatively low mobilities might be responsible for the moderate PCE. Further studies can be performed to enlarge the conjugation length by including more aromatic rings. This study provides a simple strategy to design non-fullerene acceptors and a valuable reference for the future development of PSCs. 相似文献
8.
Zhang Yingzhu Chen Jiehuan Lian Xiaomei Yang Weitao Li Jun Tian Shuoxun Wu Gang Chen Hongzheng 《中国科学:化学(英文版)》2019,62(7):859-865
Layered two-dimensional(2D)perovskite solar cells(PVSCs)with a chemical formula of C(NH_2)_3(CH_3NH_3)_3Pb_3I_(10)(n=3)have been fabricated through additive engineering,wherein stoichiometrically equivalent guanidinium(GA~+)and methylammonium(MA~+)serve as spacer cations.The crystallinity of the perovskite films is dramatically enhanced with proper amount of methylammonium thiocyanate(MASCN)added into the precursor solution.In addition,we substitute a small amount of MA~+with hydrophobic phenylethylammonium(PEA~+),which can passivate trap states of the perovskite films.As a result,the open circuit voltage increases to 1.1 V and the best power conversion efficiency(PCE)of 10.12%is yielded.Furthermore,superior thermal stability and balanced moisture stability of the PEA-substituted GA-based PVSCs are demonstrated,compared to the popular 3D MAPbI_3and 2D PEA-based PVSCs.They retain approximately 80%of the original PCE after 30 d at 20%relative humidity(RH),and 50%of the original PCE after 3200 min at 85°C without any encapsulation.This work suggests a new route to achieve both heat and humidity stable PVSCs by simply mixing different spacer cations. 相似文献
9.
研究数据链系统中的组网与数据传输技术,对于构建自主的数据链系统以及数据链系统的测试、评估极为关键。同时,进一步验证所设计的数据链系统的有效性、理解数据链的主要功能与性能参数,为进一步研究与设计测控数据链技术奠定基础。对数据链系统及数据链组网与数据传输技术进行了分析,并简要介绍不同数据链系统的组网与数据传输技术的差别,在此基础上提出一种数据链组网与数据传输仿真系统方案,对系统的功能和工作过程进行了分析,为数据链的构建、测试及评估提供支持。最后,对数据链及其测试评估系统构建及发展趋势进行了展望。该研究在数据链测试仿真评估系统中的验证效果良好,从而为数据链系统的设计提供了参考和依据。 相似文献
10.
Wei Shi Changshui Fang Feng Li Qiwei Pan Qintian Gu Dong Xu Hongzheng Wei Jinzhong Yu 《Optics and Lasers in Engineering》2000,33(1)
The polyetherketone (PEK-c) guest–host polymer planar waveguides doped with (4′-nitro)-3-azo-9-ethyl-carbazole (NAEC) were prepared. The waveguide films were poled by corona-onset poling at elevated temperature (COPET), and the corona poling setup includes a grid voltage making the surface-charge distribution uniform. By using the prism-in coupling method, the dark-line spectrum given by the reflected intensity versus the angle of incidence have been obtained, and the optical transmission losses of mth modes have been measured for the poled polymer waveguides at λ=632.8 nm. The measurement result showed that the optical loss of the fundamental mode is less than 0.7 dB cm−1 for the TE polarization. 相似文献