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We reported the fabrication and doping effect of Ga-doped ZnO nanorods/electropolymerized polythio-phene(e-PT) hybrid photovoltaic(h-PV) devices. Ga-Doped ZnO nanorod array photoanode devices were fabricated via hydrothermally growing nanorods on sol-gel spin-coating ZnO seed layer, and then the nanorod array was immersed into a thiophene solution to yield a thin polythiophene film by electrochemically polymerization. Afterwards, a thin layer of Al was deposited on the surface of polythiophene to make an electrode for photovoltaic measurement. The ZnO nanorods with different Ga-doping contents were characterized by means of X-ray diffraction(XRD), scanning electron micrograph(SEM) and X-ray photoelectron spectroscopy(XPS). Photovoltaic J-V characterization was performed on the e-PT/ZnO bilayer and bulk heterojunction(BHJ) devices. Though the unsubstituted polythiophene is not an ideal polymer material for solar cells with high power conversion efficiency, it is a sound model for the study on the effect of dopant in hybrid materials. The results indicate that doping Ga can substantially improve the power conversion efficiency of the ZnO-polythiophene solar cell. 相似文献
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高分子负载钯金属的非均相催化C—C偶联反应 总被引:1,自引:0,他引:1
本文主要介绍近年来高分子材料负载的钯金属在非均相催化C—C键偶联反应中的研究与应用。此类催化剂具有较高的活性、选择性和多次重复使用的稳定性,在催化反应膜器件、自动化的组合化学合成和实现向环境友好型的材料转化等方面有突出的发展前景。催化剂微囊化和纳米团簇化都是获取较高的活性和回收率的手段。使用高分子配体的优点是能直接固定金属,并通过不同的配位原子调节控制钯的活性,甚至呈现相应的小分子配合物不能催化的高分子效应,而高分子链本身还可以提供反应所需的良好机械性能和对不同反应介质的亲合性。 相似文献
124.
Existence of nonoscillatory solutions for system of fractional differential equations with positive and negative coefficients 下载免费PDF全文
Youjun Liu Huanhuan Zhao Huiqin Chen Shugui Kang 《Journal of Applied Analysis & Computation》2019,9(5):1940-1947
In this paper we consider the system of fractional differential equations with positive and negative coefficients. We use the $Banach$ contraction principle to obtain new sufficient conditions for the existence of nonoscillatory solutions. 相似文献
125.
Iterative solutions of the split common fixed point problem for strictly pseudo-contractive mappings
In this paper, we study the the split common fixed point problem in Hilbert spaces. We establish a weak convergence theorem for the method recently introduced by Wang, which extends a existing result from firmly nonexpansive mappings to strictly pseudo-contractive mappings. Moreover, our condition that guarantees the weak convergence is much weaker than that of Wang’s. A strong convergence theorem is also obtained under some additional conditions. As an application, we obtain several new methods for solving various split inverse problems and split equality problems. Numerical examples are included to illustrate the applications in signal processing of the proposed algorithm. 相似文献
126.
Xin Wang Licheng Bai Jiang Lu Xue Zhang Danni Liu Huanhuan Yang Jiahong Wang Paul K. Chu Seeram Ramakrishna Xue‐Feng Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19236-19242
Modulation of the electronic structure of metal catalysts is an effective approach to optimize the electrocatalytic activity. Herein, we show a surprisingly strong activation effect of black phosphorus (BP) on platinum (Pt) catalysts to give greatly enhanced catalytic activity in the hydrogen evolution reaction (HER). The unique and negative binding energy between BP and Pt leads to spontaneous formation of Pt‐P bonds producing strong synergistic ligand effects on the Pt nanoparticles. No Pt‐P bonds are formed with red phosphorus which is another allotrope of P. By controlling the number of Pt‐P bonds, 3.5‐fold enhancement in the HER activity can be achieved from the BP‐activated Pt catalyst and the activity is 6.1 times higher than that of the state‐of‐the‐art commercial Pt/C catalyst. The BP‐activated Pt catalyst exhibits a current density of 82.89 mA cm?2 with only 1 μg of Pt in 1 m KOH at an overpotential of 70 mV. 相似文献
127.
Huanhuan Feng Tingting Zheng Mingyu Li Junwei Wu Hongjun Ji Jiaheng Zhang Weiwei Zhao Jinhong Guo 《Electrophoresis》2019,40(11):1580-1590
Microfluidics has made a very impressive progress in the past decades due to its unique and instinctive advantages. Droplet‐based microfluidic systems show excellent compatibility with many chemical and biological reagents and are capable of performing variety of operations that can implement microreactor, complex multiple core–shell structure, and many applications in biomedical research such as drug encapsulation, targeted drug delivery systems, and multifunctionalization on carriers. Droplet‐based systems have been directly used to synthesize particles and encapsulate many biological entities for biomedicine applications due to their powerful encapsulation capability and facile versatility. In this paper, we review its origin, deviation, and evolution to draw a clear future, especially for droplet‐based biomedical applications. This paper will focus on droplet generation, variations and complication as starter, and logistically lead to the numerous typical applications in biomedical research. Finally, we will summarize both its challenge and future prospects relevant to its droplet‐based biomedical applications. 相似文献
128.
Ke Li Yanchao Han Jing Li Huanhuan Xing Lei Chen Guang Li Xiaoqing Zhu Erkang Wang 《Electroanalysis》2019,31(5):922-926
In this work, molybdenum carbide (Mo2C) nanotubes were prepared via the self‐degradable template method and high‐temperature calcination, and then were successfully used to modify glassy carbon electrode (CGE) for the high‐sensitivity determination of dopamine (DA) without the inference of ascorbic acid(AA) and uric acid (UA). The surface morphology of Mo2C nanotubes has been investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Owing to the enhanced electron transfer rate and high surface area of Mo2C, the modified electrode not only exhibits very excellent electrochemical performance for DA, but also has good analytical performance for DA in the mixture with AA and UA through differential pulse voltammetry (DPV), which can be applied for DA detection with wide linear range(0.005–50 μ mol L?1) and low detection limit 0.001 μ mol L?1. The modified electrode has been applied to detect DA in DA hydrochloride injection by using standard adding method with satisfactory results. 相似文献
129.
Liu Jingwei Zhang Lin Li Huanhuan Zhao Peng Ren Peng Shi Wei Cheng Peng 《中国科学:化学(英文版)》2019,62(5):602-608
A well-designed redox-active organic linker,pyrazine-2,3,5,6-tetracarboxylate(H_4pztc)with brimming active sites for lithium ions storage was utilized to construct coordination polymers(CPs)via a facile hydrothermal reaction.Those two isostructural two-dimensional(2D)CPs,namely[M_2(pztc)(H_2O)_6]_n(M=Co for 1 and Ni for 2),delivered excellent reversible capacities and stable cycling performance as anodes in lithium ion batteries.As demonstrated in electrochemical studies,1 and 2 can achieve highly reversible capacities of 815 and 536 mA h g~(-1)at 200 mA g~(-1)for 150 cycles,respectively,best performed for the reported2D-CP-based anode materials.The electrochemical mechanism studies showed that the remarkable performances can be ascribed to the synergistic Li-storage redox reactions of metal centers and organic moieties.Our work highlights the opportunities of using a well-designed organic ligand to construct low-dimensional CPs as new type of electrode materials for advanced lithium ion batteries. 相似文献
130.
研究了氧化石墨烯(GO)对聚乙烯醇(PVA)/硼酸(borate)水凝胶线性及非线性流变性能的影响。 通过扫描电子显微镜、硼谱核磁共振波谱以及流变研究了水凝胶的流变性能。 结果表明,GO质量浓度在稀溶液区时,GO片层与PVA链间通过硼酸根离子形成了具有弹性活性的缔合点,有效地提高了水凝胶的平台模量、松弛时间和零切粘度;当GO进一步增加到亚浓溶液区,部分的交联剂被GO的团聚体捕获并处于非弹性活性的缔合状态,处于有效缔合状态的交联剂变少,导致平台模量、松弛时间和零切粘度降低。 稳态剪切测试下,样品在剪切增稠区的粘度增加随着GO添加量的增加明显加强,这与剪切场下取向的氧化石墨烯片层参与网络结构的重排有关。 相似文献