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1.
《Carbon》2015
The metal grid and reduced graphene oxide (RGO) are both promising transparent conductive materials for replacing the indium tin oxide (ITO) in flexible optoelectronics. However, the large empty area that exists in the grid together with the relatively high sheet resistance of RGO hinder both the materials for practical applications. In this work, we report for the first time a novel strategy for efficient combination of the metal grid and RGO by using a newly developed room-temperature reduction technique. The obtained RGO/metal grid hybrid films not only overcome the shortcomings of individual components but exhibit enhanced optical and electrical performances (Rs = 18 Ω sq−1 and T = 80%) and excellent flexural endurance. With this hybrid film as the window electrode, a highly flexible electrochromic device with excellent stability and ultra-fast response shorter than 60 ms has been successfully fabricated. Considering its high efficiency, high quality, low cost and large area, the strategy would be particularly useful for economically fabricating various metal grid/RGO films which are quite promising high performance transparent and conductive materials for next generation optoelectronic devices. 相似文献
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设计并制作了一种新型的SOI 2×2马赫一曾德(MZ)热光开关。这种光开关采用了深刻蚀结构的配对多模干涉耦合器,同时,为了保证单模传输和调制,在连接波导和调制臂区域采用了浅刻蚀结构。深刻蚀结构增强了多模干涉耦合器对光场的限制,有利于自映像质量的提高,从而减少了自映像损耗和不均衡度,同时也提高了制作容差。基于强限制配对干涉耦合器的新型热光开关,其插入损耗为-11.0dB,其中包括光纤波导耦合损耗4.3dB,上升和下降开关时间分别为3.5μs和8.8μs。 相似文献
4.
《Journal of power sources》2005,145(2):644-651
A WO3/CeO2/YSZ nanocomposite material [W/Zr nominal atomic ratio = 0.025, Ce/Zr nominal atomic ratio = 0.020] was prepared by wet impregnation and characterized by means of X-ray photoelectron and diffuse reflectance infrared Fourier transform spectroscopic techniques, X-ray diffraction and thermal analysis.Both tungsten and cerium oxides are significantly reduced at the interface with YSZ: Ce(III), in particular, seems to be the prevailing species.The interaction of the WO3/CeO2/YSZ nanopowder with pyridine and CO2 allowed to investigate the acidic/basic sites. Weak contributions at 1602, 1625 and 1647 cm−1 suggest the presence of Lewis and Brønsted acidic sites, whereas basic sites are not evidenced by the interaction with carbon dioxide. The presence of tungsten oxide causes the decrement of the acidic/basic sites, as indicated by the comparison with the results obtained on the CeO2/YSZ support. Consistently, the interaction with methanol is mainly molecular.The oxidation of methanol was investigated both in the absence and in the presence of water. In the last case carbon dioxide starts forming from room temperature. 相似文献
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Multi-channel micro neural probe fabricated with SOI 总被引:1,自引:0,他引:1
WeiHua Pei Lin Zhu ShuJing Wang Kai Guo Jun Tang Xu Zhang Lin Lu ShangKai Gao HongDa Chen 《中国科学E辑(英文版)》2009,52(5):1187-1190
Silicon-on-insulator(SOI) substrate is widely used in micro-electro-mechanical systems(MEMS).With the buried oxide layer of SOI acting as an etching stop,silicon based micro neural probe can be fabri-cated with improved uniformity and manufacturability.A seven-record-site neural probe was formed by inductive-coupled plasma(ICP) dry etching of an SOI substrate.The thickness of the probe is 15 μm.The shaft of the probe has dimensions of 3 mm×100 μm×15 μm with typical area of the record site of 78.5 μm2.The im... 相似文献
6.
Based on Al induced crystallization (AIC) method, influences of different material structures on formation and characteristics of ploy-silicon thin films were studied and optimized. Al-Si films on glass with different structures (Si/Al/Glass, Al/Si/Glass, Si/Al/…/Si/Al/Glass) were deposited on glass substrates by sputtering method. All samples were annealed for MIC with varied time processes under 500℃ N2 environment. X-ray diffraction test and scanning electron microscope were adopted to characterize cryst... 相似文献
7.
Summary Polypyrrole (PPy) composite films with different contents of Fe3O4 were prepared by in-situ polymerization of pyrrole in aqueous solutions. The dependence of dc current changes on the response
of the samples exposure to NH3 vapor has been investigated. The results shows the composite films are more stable than the pristine ones after being exposed
to NH3 vapor. Meanwhile, the response time was reduced with increasing the Fe3O4 content in the films. The results might be originated from the structural changes in the PPy films caused by the addition
of Fe3O4. 相似文献
8.
A compact tubular sensor based on NASICON (sodium super ionic conductor) and V2O5-doped TiO2 sensing electrode was designed for the detection of SO2. In order to reduce the size of the sensor, a thick-film of NASICON was formed on the outer surface of a small Al2O3 tube; furthermore, a thin layer of V2O5-doped TiO2 with nanometer size was attached on the NASICON as a sensing electrode. This paper investigated the influence of V2O5 doping and sintering temperature on the characteristics of the sensor. The sensor attached with 5 wt% V2O5-doped TiO2 sintered at 600 °C exhibited excellent sensing properties to 1–50 ppm SO2 in air at 200–400 °C. The EMF value of the sensor was almost proportional to the logarithm of SO2 concentration and the sensitivity (slope) was −78 mV/decade at 300 °C. It was also seen that the sensor showed a good selectivity to SO2 against NO, NO2, CH4, CO, NH3 and CO2. Moreover, the sensor had speedy response kinetics to SO2 too, the 90% response time to 50 ppm SO2 was 10 s, and the recovery time was 35 s. On the basis of XPS analysis for the SO2-adsorbed sensing electrode, a sensing mechanism involving the mixed potential at the sensing electrode was proposed. 相似文献
9.
Pure and Sm2O3-doped SnO2 are prepared through a sol–gel method and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The sensor based on 6 wt% Sm2O3-doped SnO2 displays superior response at an operating temperature of 180 °C, and the response magnitude to 1000 ppm C2H2 can reach 63.8, which is 16.8 times larger than that of pure SnO2. This sensor also shows high sensitivity under various humidity conditions. These results make our product be a good candidate in fabricating C2H2 sensors. 相似文献
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