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41.
C. Navone S. Tintignac J.P. Pereira-Ramos R. Baddour-HadjeanR. Salot 《Solid State Ionics》2011,192(1):343-346
Here are reported for the first time electrochemical data on all-solid-state lithium microbatteries using crystalline sputtered V2O5 thin films as cathode materials and LiPON as solid electrolyte. The stable specific capacity of 30 µAh/cm2 found with a 2.4 µm thick film competes very well with the best values obtained for solid state microbatteries using amorphous films. With the challenge of decreasing the temperature of heat treatment for sputtered LiCoO2 thin films, we show that a temperature of 500 °C combined with an optimized bias sputtering (-50 V) allows to get highly crystalline deposits, to minimize the presence of Co3O4 and to suppress any trace of the cubic phase. At the same time the theoretical specific capacity is reached in the 4.2 V-3 V range and a good cycling behaviour is achieved with a high capacity of 50 µAh/cm2/µm after 140 cycles at 10 µA.cm2. 相似文献
42.
在气体流动管中对三氯化氮气体喷射自发分解的现象进行了初步实验研究。在一根长80 cm,直径4 cm的圆柱形石英玻璃管中,用喷嘴向气体流动管内喷射NCl3/He混合气体,观察到了NCl3喷射分解时的红色火焰。测量了火焰光谱并进行了归属,认为该光谱是Cl2(B→X)辐射跃迁。NCl3的喷射自发分解本质上是激波诱导发生的,即分子的动能转化为分子内能而引起的,生成的Cl原子及NCl2自由基与NCl3分子反应,从而得到持续燃烧火焰。实验结果表明了NCl3自发分解反应可代替放电或燃烧作为Cl原子的来源。 相似文献
43.
Titanium dioxide (TiO2) nanoparticles co-doped with N and Fe were prepared via modified sol-gel process. The products were characterized by transmission electron microscopy (TEM), N2 adsorption, X-ray diffraction (XRD), Raman spectroscopy, UV-vis spectroscopy, photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS). It is shown that the prepared TiO2 particles were less than 10 nm with narrow particle size distribution. The addition of MCM-41 caused the formation of Ti-O-Si bond which fixed the TiO2 on MCM-41 surface, thus restricted the agglomeration and growth of TiO2 particles. The photocatalytic performance in the degradation of methylene blue showed that N, Fe co-doped TiO2 exhibited much higher photocatalytic activity than doped sample with nitrogen or Fe3+ alone under both UV and visible light. N, Fe co-doping decreased the loss of doping N during the degradation reaction, thus increased the photocatalytic stability. It was also found that the nitridation time had significant influence on the photocatalytic activity of prepared TiO2 catalysts. 相似文献
44.
The processes of electron transfer and dissociative scattering are explored for collisions of hyperthermal NO+ on GaAs(110). The experiments reveal a marked angular dependence to O− emergence. A strong correlation between the O− scattering angle and the final atom-surface interaction site provides a map of the lateral dependence to reactivity. The results are modeled by sequential neutralization, dissociation, and electron attachment steps. Classical trajectory calculations, in conjunction with an empirical opacity function, accurately reproduce the experimental results. The opacity function is interpreted as the probability that an electron will attach to a departing O fragment as a function of the last surface site the atom impacts. The experiments indicate that O− emergence occurs predominantly for oxygen atoms which come in close contact with the localized dangling bond states of GaAs(110). 相似文献
45.
46.
Iron oxides (haematite, maghemite, magnetite), (oxy)hydroxides (lepidocrocite), carbonates, as well as zinc carbonate and oxide, have been identified on corroded galvanized steel samples after corrosion accelerating tests in the laboratory and compared with those observed on samples taken from vehicles that have been in circulation for five years in severe weather conditions. Spectra recorded on the corroded parts are compared with synthesized compounds. (Hydroxy)carbonates are clearly evidenced on galvanized and phosphated steel sheets. Corrosion layers beneath the paint could be detected. White regions always correspond to a ZnO‐rich phase but maghemite (γ‐Fe2O3) and sometimes akaganite (β‐FeOOHCl) are observed at the centre (maroon) of very corroded spots. Maghemite is observed in strongly corroded regions. Goethite (α‐) and lepidocrocite (γ‐FeOOH) (and akaganite) are observed at the surface of less corroded regions of phosphate‐free galvanized steel and are absent for phosphate‐coated steel. Green rust is observed only on galvanized samples corroded in the laboratory. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
47.
本文通过固相反应方法制备了具有钙钛矿结构的稀土掺杂锰氧化物La0.875Sr0.125MnO3(LSMO)块材,并用磁控溅射方法在LaAlO3衬底上生长了厚度为50nm的单晶薄膜.X射线衍射仪分别对LSMO块材和薄膜材料进行分析,表明薄膜和衬底具有相同的钙钛矿结构;通过研究该薄膜光诱导效应和磁场下输运行为,发现其输运性质明显改变,表明外场改变体系的电子自旋输运特性,引起双交换作用减弱和增强,分别导致电阻率的增加和减小. 相似文献
48.
We report the results of the DC magnetization, neutron powder diffraction and neutron depolarization studies on the spin-chain
compounds Ca3Co2–x
Fe
x
O6 (x = 0, 0.1, 0.2 and 0.4). Rietveld refinement of neutron powder diffraction patterns at room temperature confirms the single-phase
formation for all the compounds in rhombohedral structure with space group Rc. Rietveld refinement also confirms that Fe was doped at the trigonal prism site, 6a (0, 0, 1/4) of Co. The high temperature
magnetic susceptibility obeys the Curie-Weiss law; the value of the paramagnetic Curie temperature (θ
p) decreases as the concentration of iron increases and it becomes negative for x = 0.4. No extra Bragg peak as well as no observable enhancement in the intensity of the fundamental (nuclear) Bragg peaks
has been observed in the neutron diffraction patterns down to 30 K. No depolarization of neutron beam has been observed down
to 3 K confirming the absence of ferro- or ferrimagnetic-like correlation.
相似文献
49.
Liwei Chen Prof. Dr. Jinkee Hong Prof. Dr. Hans-Jürgen Butt Prof. Dr. Sanghyuk Wooh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(18):4535-4542
Metal oxide photocatalysts (MOPCs) decompose organic molecules under illumination. However, the application of MOPCs in industry and research is currently limited by their intrinsic hydrophilicity because MOPCs can be wetted by most liquids. To achieve liquid repellency, the surface needs to possess a low surface energy, but most organic molecules with low surface energy are degraded by photocatalytic activity. Herein, current methods to achieve liquid repellency on MOPCs, while preventing degradation of hydrophobic coatings, are reviewed. Classically, composite materials containing MOPCs and hydrophobic organic compounds possess good liquid repellency. However, composites normally form irregular coatings and are hard to prepare on surfaces such as those that are mesoporous or nanostructured. In addition, the adhesion of composites to substrates is often weak, resulting in delamination. Recent studies have shown that the direct grafting reaction of polydimethylsiloxane (PDMS) from silicone oil (methyl-terminated PDMS) under illumination results in a stable polymer brush. This easy and simple grafting method allows us to create stable liquid-repellent surfaces on MOPCs of various types, structures, and sizes. In particular, super-liquid-repellent drops with an underlying air layer can be created on PDMS-grafted nano-/microstructured MOPCs. Potential applications of surfaces combining liquid repellency and photocatalytic activity are also discussed; thus offering new ways of using MOPCs in a wider range of applications. 相似文献