高质量氧化铝模板的制备及其研究

以5%磷酸为电解液,通过阳极氧化高纯铝片制得了有序性较高的多孔氧化铝模板,结合扫描电镜(SEM)对其结构和行貌进形观察和表征.研究了氧化铝模板的制备工艺,还讨论了氧化铝膜的形成过程,最后比较了一次阳极氧化和二次阳极氧化获得的样品的多孔结构,认为低温下采用二次阳极氧化法可以获得很好的多孔氧化铝模板.     

纯钛表面两步电化学法制备载银多孔涂层

在医用纯钛表面先采用阳极氧化法制备TiO2纳米管预涂层,然后通过AgNO3溶液浸泡和紫外光照射处理实现银颗粒在预涂层上的固定,再经过微弧氧化处理制备出载银多孔涂层。利用扫描电子显微镜(SEM)、能谱仪(EDS)、X射线光电子能谱(XPS)对涂层表面形貌、载银量、银元素纵向分布及特征进行了表征,并通过金黄色葡萄球菌检验了涂层的抗菌性能。结果表明:两步电化学法可以在纯钛表面制备出含银量较高的多孔涂层,涂层中银元素大部分以纳米颗粒形式存在,涂层表面和最外层Ag元素主要以氧化物的形式存在,而沿涂层法向向内Ag单质与Ag氧化物共存,且涂层具有良好的抗菌性能。     

Organic Thin‐Film Transistors with Anodized Gate Dielectric Patterned by Self‐Aligned Embossing on Flexible Substrates

An upscalable, self‐aligned patterning technique for manufacturing high‐ performance, flexible organic thin‐film transistors is presented. The structures are self‐aligned using a single‐step, multi‐level hot embossing process. In combination with defect‐free anodized aluminum oxide as a gate dielectric, transistors on foil with channel lengths down to 5 μm are realized with high reproducibility. Resulting on‐off ratios of 4 × 10⁶ and mobilities as high as 0.5 cm² V^?1 s^?1 are achieved, indicating a stable process with potential to large‐area production with even much smaller structures.     

Porous silicon/Ni composites of high coercivity due to magnetic field assisted etching

ABSTRACT: Ferromagnetic nanostructures have been electrodeposited within the pores of porous silicon templates with average pore-diameters between 25 and 60 nm. In this diameter regime the pore-formation in general is accompanied by dendritic growth resulting in rough pore-walls which involves metal deposites also offering a branched structure. These side-branches influence the magnetic properties of the composite system not only due to modified and peculiar stray fields but also because of a reduced interpore-spacing by approaching of adjacent side-pores. To improve the morphology of the porous silicon structures a magnetic field up to 8 T has been applied during the formation process. The magnetic field etching results in smaller pore-diameters with less dendritic side-pores. Deposition of a ferromagnetic metal within these templates leads to less branched nanostructures and thus to an enhancement of the coercivity of the system and also to a significantly increased magnetic anisotropy. So magnetic field assisted etching is an appropriate tool to improve the structure of the template concerning the decrease of the dendritic pore-growth and to advance the magnetic properties of the composite material.     

Tunable Fabry-Pérot interferometer based on nanoporous anodic alumina for optical biosensing purposes

ABSTRACT: Here, we present a systematic study about the effect of the pore length and its diameter on the specular reflection in nanoporous anodic alumina. As we demonstrate, the specular reflection can be controlled at will by structural tuning (i.e., by designing the pore geometry). This makes it possible to produce a wide range of Fabry-Pérot interferometers based on nanoporous anodic alumina, which are envisaged for developing smart and accurate optical sensors in such research fields as biotechnology and medicine. Additionally, to systematize the responsiveness to external changes in optical sensors based on nanoporous anodic alumina, we put forward a barcode system based on the oscillations in the specular reflection.     

永冲电化学腐蚀制备n型多孔硅及其发光性能

采用脉冲电化学腐蚀法,以n型单晶硅为衬底制备多孔硅（n—PS）,通过扫描电镜（SEM）、室温500—700nm范围内荧光光谱,系统研究腐蚀时间、占空比和脉冲频率对n-PS的结构形貌和可见光区室温光致发光特性（PL）的影响,结果表明,相比直流电化学腐蚀方法,脉冲腐蚀能获得孔径分布均匀且发光强度更高的多孔硅;随腐蚀时间、占空比和脉冲频率等腐蚀条件的变化,其发光峰位及发光强度均有明显改变;当等效腐蚀时间为30min、占空比为0．5、脉冲频率为10Hz时,制备的n—PS的PL强度较高,发光性能较好。     

电解液对TiO2纳米管阵列薄膜光电催化性能的影响

采用电化学阳极氧化法,在HF—H2O,NH4F—H2O,NH4F—H2O-乙二醇三种不同的电解液体系中,于Ti基底上制备了TiO2纳米管阵列薄膜,并在空气气氛中于500℃进行结晶热处理。以亚甲基蓝为模拟污染物,考察了TiO2纳米管阵列薄膜的光电催化降解效果,并比较了电解催化、光催化和光电催化对亚甲基蓝溶液降解效率的差异。结果表明在NH4F—H2O-乙二醇电解液体系中制备的TiO2纳米管阵列光电催化性能最好。经过340min后,催化效率达到了94．23％。     

A One‐Step and Binder‐Free Method to Fabricate Hierarchical Nickel‐Based Supercapacitor Electrodes with Excellent Performance

Research is currently being carried out in the search for alternative electrode materials to replace the expensive and toxic RuO₂‐based electrode. As a typical example, nickel oxide or hydroxide has been widely studied but the results are far from satisfactory. Here, using a facile one‐step anodization method, a hierarchical nickel compound (HNC) film with an interconnecting 3D nanoflake structure is obtained, providing large electrochemically active surface area and interconnecting nanoscale pore channels for ion transport. The HNC electrode demonstrates significantly improved capacitance, 70 times higher than the reported NiO‐TiO₂ nanotube array electrode with similar thickness. The charge/discharge kinetics are also superior, showing only a 24% capacitance reduction when the scan rate is increased by 50 times, as compared with the typical 70% capacitance reduction for pseudocapacitor electrodes under the same conditions. HNC exhibits an extraordinary excellent cycle life; capacitance increases to 115% after 4500 test cycles. Furthermore, because HNC is in intimate contact with the current collector, it is not necessary to use conducting agents or binders, which reduces the electrode weight and facilitates the electrode preparation process. The method is low cost, facile, scalable, additive free, and is promising for fabricating supercapacitor electrode with excellent performance.     

TiO2纳米管光电极的制备及其光电催化性能研究

采用阳极氧化法在Ti箔上原位生成了TiO2纳米管光电极,并利用SEM和XRD对样品的表观形貌和晶相结构进行了表征。结果表明:TiO2纳米管管口均匀,管径为90~100 nm,且具有单一的锐钛矿晶相。此外,重点考察了初始pH值和外加偏压对TiO2纳米管光电极光电流响应及光电催化活性的影响。结果表明:当溶液pH为7.5、外加偏压为2.0V时,光电流响应最强,为10.4 mA·cm-2。350 W氙灯下光照60 min对罗丹明B的光电催化降解效率可达82.6%。