Electrochemical synthesis of silver nanoparticles-coated gold nanoporous film electrode and its application to amperometric detection for trace Cr(VI)

A simple and rapid approach for the electrochemical synthesis of Ag nanoparticles-coated gold nanoporous film (AgGNF) on a gold substrate was reported. The solid gold electrode (SGE) was directly anodized under a high potential of 5 V, and then reduced to obtain gold nanoporous film (AuNF) by freshly prepared ascorbic acid. The Ag nanoparticles (AgNPs) were grown on the AuNF electrode by potential-step electrodeposition. The resulting AgGNF composites electrodes were characterized by scanning electron micro...     

低介电常数介质薄膜的研究进展

用低介电常数介质薄膜作金属线间和层间介质可以降低超大规模集成电路(ULSI) 的互连延迟、串扰和能耗。从介质极化的原理出发,揭示了开发低介电常数介质薄膜的可能途径;综述了低介电常数介质薄膜的制备方法、结构与性能表征、工艺兼容性等领域的最新进展。     

Ultra Compact Nanoporous Platinum Coating Improves Neural Recording

Neural electrodes are key tools for achieving a successful brain-computer interface and the electrodes should be small to minimize damage to neural tissue and obtain good spatial selectivity such as single unit recording. Here we show conventional platinum/tungsten neural probes can be coated with nanoporous Pt. Thanks to nanoporous Pt with the extremely small and uniform pores, L₂-ePt, the electrode impedance could be reduced by more than 2 orders of magnitude while the apparent area was almost the same. L₂-ePt coating enhanced neuronal recording of local field potential in monkeys, leading to facilitating implanted electrical devices in the nervous system.     

The Mechanical Deformation Process of Electrospun Polymer Nanocomposite Fibers

Summary: The mechanical deformation processes of poly(methyl methacrylate)/ montmorillonite nanocomposites and their electrospun fibers were investigated by in situ tensile tests under a transmission electron microscope depending on their morphology. While the polymer nanocomposites deformed in a brittle manner, i.e., crazing, the electrospun polymer nanocomposite fibers deformed through a shear flow process leading to “nanonecking” due to the strong overlap of stress fields caused by nanopores within the fiber under a uniaxial tensile load. This unique change in deformation behavior provides the possibility that the intrinsic brittle material could be manipulated to be ductile without sacrificing its other attractive properties through a well‐controlled electrospinning process.

TEM micrograph of a low temperature fractured fiber showing the nanoporous surface structure.     

Synthesis and Characterization of Novel Poly-thiophene-nanoporous Silica and its Application for Mercury Removal from Waste Waters

In this work, MCM-41 (Mobil Composition of Matter number 41) nanoporous silica has been synthesized and characterized by X-ray powder diffraction and IR spectroscopy. In the next step, poly-thiophene was coated on the nanoporous silica in order to increase its surface area. This composite was characterized by X-Ray powder diffraction, High resolution transmission electronic microscopy micrograph (HRTEM), elemental analysis (CHNS) and Thermal analysis (TG/DTA). The application of this composite was investigated in mercury ions removal from waste water prior to determination by inductively coupled plasma atomic emission spectroscopy (ICP-OES). In order to investigate the effect of nanoporous structure on the efficiency of this composite, the same composite without porous structure has been synthesized and the results were compared.     

脱合金制备纳米多孔双金属氧化物NiMoO_4及其电化学性能

采用快速凝固与脱合金相结合的方法制备纳米多孔Ni-Mo合金,然后退火获得三维双连续纳米多孔NiMoO_4,采用XRD、SEM、TEM对多孔NiMoO_4的成分、形貌和结构进行表征,并通过循环伏安、恒电流充放电等方法测试多孔NiMoO_4电极的电化学性能。结果表明,Ni_5Mo_5Al_(90)和Ni_(2.5)Mo_(2.5)Al_(95)经脱合金和退火均可获得纳米多孔NiMoO_4,Mo元素对脱合金具有钉扎作用,可减小多孔合金的骨架和孔隙尺寸,由Ni_5Mo_5Al_(90)合金获得纳米多孔NiMoO_4表现出更为优异的超电容性能,其在1 A·g~(-1)电流密度比容量达708 F·g~(-1),当电流密度增加20 A·g~(-1),其比容保持率达57.1%。在4 A·g~(-1)电流密度下循环充放电1 000次,其比容保持率达91.2%。     

Solid‐state microcellular and nanocellular polysulfone foams

In this article, we report on the process for creating microcellular and nanocellular polysulfone (PSU) foams. Microcellular foams with cell size up to 8 µm and nanocellular foams with cell size in the range of 20–30 nm were created. A range of CO₂ concentration was achieved by varying saturation temperature, from 5% at 60 °C to 14.7% at ?10 °C. The CO₂ concentration has a strong influence on the cellular structure. There exists a critical concentration window, between 10.7% and 12.3%, within which cell nucleation densities increase rapidly and cell sizes drop from micrometer range to below 1 µm into the nanometer range. Nanofoams with cell nucleation densities exceeding 10¹⁵ cells/cm³ and void fraction of up to 48% are achieved. At the high CO₂ concentration region, the change from closed nanocellular structure to bicontinuous nanoporous structure is observed. Also, nanostructures on the cell wall of microcells are observed and believed to be formed via stress‐induced nucleation/spinodal decomposition. The PSU nanofoams produced in this study present an opportunity to produce polymer nanofoams with a relatively high service temperature. The ability to create cells of different length scales provides an opportunity to study the effect of cell size on the foams properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 975–985