真空蒸镀法制备锡薄膜及其嵌锂电化学性能

采用真空蒸镀法在铜片基底上沉积锡薄膜作为锂离子电池负极材料,对所制备的锡薄膜采用扫描电子显微镜、X射线衍射表征,研究了其表面形貌和组成。 将制备的薄膜在手套箱中组装成CR2032型钮扣式电池,进行电化学测试,研究其电化学性能。 实验结果表明,在相同蒸发时间和基底温度的条件下,随着蒸发功率的增加,沉积的锡颗粒逐渐增大,相应的电化学性能降低。 以蒸发功率200 W、基底温度150 ℃制得的样品粒径为100~200 nm,含有Cu6Sn5合金相,以0.2C倍率充放电循环20周后放电容量达527 mA·h/g。     

Fabrication of superhydrophobic silica film by removing polystyrene spheres

A superhydrophobic silica film has been fabricated by a facile method, which combines the co-sedimentation of dual-sized polystyrene (PS) spheres and the infiltration of a silica sol. The scanning electron microscopy (SEM) observations indicate that the as-prepared silica surface has a hierarchical micro/nano-structure. The micrometer-sized hollow silica particle with nanometer-sized holes on its surface was created by removing the organic polymer at high temperature. After chemically modified by a layer of dodecafluoroheptyl-methyl-dimethoxysilane (DFMS), the silica film has a water contact angle up to 156.4°, showing excellent superhydrophobic property. The present method may enhance widespread application of superhydrophobic film because of its simplicity and cheapness.     

Silver hierarchical bowl-like array: synthesis, superhydrophobicity, and optical properties

We present a facile synthetic route to a silver bowl-like array film with hierarchical structures on glass substrate using the colloidal monolayer as a template. In these special hierarchical structures, microstructures were provided by a colloidal template of polystyrene latex spheres and nanostructures resulting from the thermal decomposition of silver acetate. These structures were chemically modified with 1-hexadecanethiol, and a corresponding self-assembled monolayer (SAM) was formed on their surfaces. Due to the lotus leaf-like morphology with hierarchical micro/nanostructures, the film displayed an extraordinary superhydrophobicity after chemical modification. Water contact angle and sliding angle were 169 degrees and 3 degrees (the weight of water droplets: 3 mg), respectively. Additionally, its optical property has also been investigated. This structure could be used in microfluidic devices, optical devices, and biological science.     

Free-standing aluminium nanowire architectures made in an ionic liquid

We report on the electrochemical synthesis of free‐standing aluminium nanowire architectures through a template‐assisted electrodeposition technique. For this purpose, nuclear track‐etched polycarbonate membranes were employed as templates. One side of the template was sputtered with a thin gold film to serve as a working electrode. Subsequently the nanowires were made in the ionic liquid 1‐ethyl‐3‐methylimidazolium chloride ([EMIm]Cl)/AlCl₃ (40/60 mol %) under potentiostatic conditions. Two different electrodeposition procedures were employed to fabricate strongly adherent Al nanowire structures on an electrodeposited Al layer. In the first procedure, electrodeposition simultaneously occurs along the pores of the template and on the Au‐sputtered side of the template. In the second procedure, electrodeposition takes place in two different steps: first a thick supporting film of Al is deposited on the sputtered side of the membrane and second Al nanowires are grown within the pores. After chemical dissolution of the membrane in dichloromethane, an aluminium foil of a controlled thickness with a three‐dimensional nanowire structure on one side was obtained. Different nanowire architectures, such as free‐standing nanowires, vertically aligned tree‐shaped arrays, and bunched nanowire films, were obtained. Such nanowire architectures are of particular interest for applications in Li‐ion micro‐batteries.     

纳米银碗阵列结构的高效制备及荧光增强性能

报道了一种以自组装单层聚苯乙烯纳米微球阵列为模板, 通过真空热蒸镀银纳米粒子高效制备大面积银碗阵列结构的方法. 测试结果表明, 制得的银碗阵列结构为微纳米复合分级结构, 银碗由平均粒径为10 nm的银纳米粒子组成. 紫外-可见吸收光谱测试结果表明, 银碗阵列结构表面具有银纳米粒子的局域表面等离子体共振吸收峰. 将荧光分子N,N'-二正丁基喹吖啶酮(DBQA)分别蒸镀到普通银膜和银碗阵列结构表面并测试了荧光光谱. 结果表明, 在银碗阵列结构表面的荧光分子强度得到了显著增强, 说明制备的银碗阵列结构是优良的荧光增强基底.     

双层分等级TiO_2纳米线制备及其光伏性能研究

采用两步溶剂热反应制备了底层为分等级锐钛矿的TiO_2纳米线阵列,上层为分等级锐钛矿的TiO_2纳米线薄膜的双层结构电极.通过XRD和SEM对其组成和形貌进行了表征,并考察了纳米线薄膜对染料敏化太阳电池(DSSC)光伏性能的影响.实验结果表明,分等级锐钛矿的TiO_2纳米线作为DSSC的光阳极,光电转换效率为4.39%,其效率高于光滑的TiO_2纳米线光阳极电池效率(2.07%).     

Facile fabrication of a superhydrophobic surface from natural Eucommia rubber

In this study, we introduce a fabrication method for a superhydrophobic surface made from natural Eucommia rubber. Based on the Eucommia rubber extract solution, we prepared a type of superhydrophobic material using the simple phase separation method and the addition of a low‐surface‐energy substance method, thus developing a new approach for the application of natural Eucommia rubber. The experimental results showed that a superhydrophobic film could be obtained by both the addition of acetone and induction by water vapor. Additionally, the film exhibited properties closely related to the crystalline Eucommia rubber spherical particles with a hierarchical structure. The addition of hydrophobic silica also increased the hydrophobic property of the Eucommia rubber film. When the content of the silica was 4% (wt%), the contact angle of the composite film reached 160.7°, which could be attributed to the properties of the nano‐silica and the micro‐nano structure of the composites. Copyright © 2017 John Wiley & Sons, Ltd.     

Interfacial Molecular Imprinting in Nanoparticle-Stabilized Emulsions

A new interfacial nano and molecular imprinting approach is developed to prepare spherical molecularly imprinted polymers with well-controlled hierarchical structures. This method is based on Pickering emulsion polymerization using template-modified colloidal particles. The interfacial imprinting is carried out in particle-stabilized oil-in-water emulsions, where the molecular template is presented on the surface of silica nanoparticles during the polymerization of the monomer phase. After polymerization, the template-modified silica nanoparticles are removed from the new spherical particles to leave tiny indentations decorated with molecularly imprinted sites. The imprinted microspheres prepared using the new interfacial nano and molecular imprinting have very interesting features: a well-controlled hierarchical structure composed of large pores decorated with easily accessible molecular binding sites, group selectivity toward a series of chemicals having a common structural moiety (epitopes), and a hydrophilic surface that enables the MIPs to be used under aqueous conditions.     

Dewetting behavior of a block copolymer/homopolymer thin film on an immiscible homopolymer substrate

Numerous previous studies have established that the addition of a microphase-ordered AB diblock copolymer to a thin homopolymer A (hA) film can slow, if not altogether prevent, film rupture and subsequent film dewetting on a hard substrate such as silica. However, only a few reports have examined comparable phenomena when the hA/AB blend resides on a soft B-selective surface, such as homopolymer B (hB). In this work, the dewetting kinetics of thin films composed of polystyrene (PS) and a symmetric poly(styrene-b-methyl methacrylate) (SM) diblock copolymer on a poly(methyl methacrylate) substrate is investigated by hot-stage light microscopy. Without the SM copolymer, the dewetting rate of the PS layer is constant under isothermal conditions and exhibits Arrhenius behavior with an apparent activation energy of approximately 180 kJ/mol. Addition of the copolymer promotes a crossover from early- to late-stage dewetting kinetics, as evidenced by measurably different dewetting rates. Transmission electron microscopy reveals the morphological characteristics of dewetted PS/SM films as functions of film thickness and SM concentration.     

Biomimetic fabrication of lotus-leaf-like structured polyaniline film with stable superhydrophobic and conductive properties

Superhydrophobic surfaces were successfully prepared on Ti/Si substrates via the fabrication of conductive polyaniline (PANI) nanowire film. The PANI nanowire film was synthesized by electrodeposition of aniline into the pores of an anodic aluminum oxide (AAO) template on Ti/Si substrate followed by the removal of the template. The surface showed conductivity and superhydrophobicity, even in many corrosive solutions, such as acidic or basic solutions over a wide pH range. Field emission scanning electron microscopy (FE-SEM) demonstrated that the binary geometric structures at micro- and nanometer scale bestowed the prerequisite roughness on the surfaces. The chemical surface modification made the PANI nanowire film superhydrophobic. The results demonstrated that the PANI nanowire film will have good potential applications in the preparation of conductive superhydrophobic surfaces.     

Nano silver coated patterned silica thin film by sol–gel based soft lithography technique

We report the fabrication of nano silver coated patterned silica thin film by sol–gel based soft lithography technique. Initially, silica gel film on soda lime silica glass was prepared by dipping technique from a silica sol of moderate silica concentration. A PolydimethylSiloxane elastomeric stamp containing the negative replica of the patterns of commercially available compact disc was used for embossing the film and the embossed film was cured up to 450 °C in pure oxygen atmosphere for oxide film. Finally, a precursor solution of AgNO₃ in water containing polyvinyl alcohol as an organic binder was made and used for coating on the patterned silica film by dipping technique and cured the sample up to 450 °C in reducing gas atmosphere to obtain nano silver layer. The formation of only cubic silver (~4.0 nm) and both cubic silver (~5.2 nm) and silver oxide (~3.6 nm) crystallites at 350 and 450 °C film curing temperatures respectively were confirmed by XRD measurements. The % of nano silver metal and silver oxide were 75.4 and 24.6 respectively. The nano-structured surface feature was visualized by FESEM whereas AFM revealed the high fidelity grating structure of the films. Presence of both spherical and rectangular structure (aspect ratio, 2.37) of nano silver/silver oxide was confirmed by TEM. The films were also characterized by UV–Vis spectral study. The patterned film may find application in chemical sensor devices.     

Formation of AlOOH and silica composite hierarchical nanostructures thin film by sol–gel dip-coating for superhydrophobic surface with high adhesion force

Nanosheet AlOOH and silica spheres composite thin film was deposited onto glass by sol–gel dip-coating method through hydrolysis of boiling water immersion. A silica sol and an alumina sol are employed in dipping process for the preparation of hierarchical nanostructures thin film. The morphology and structure of the films were characterized using field emission scanning electron microscopy and X-ray diffraction. The super-hydrophobicity with high adhesion forces can be attributed to both the rough multi-scale structural coating and surface enrichment of low surface energy with the chemical vapor deposition of 1H,1H,2H,2H-perfluorodecyltriethoxysilane.     

激光刻蚀模板中电沉积特殊结构CIGS薄膜

本文利用激光刻蚀模板,在水溶液中电沉积制备金属铜薄膜,讨论了温度、电流、硫酸铜浓度对薄膜形貌的影响. 采用SEM对制备的铜薄膜进行表征,结果表明在沉积温度为30 ℃,沉积电流为4 A·dm^-2(表观工作电流密度),硫酸铜浓度在20 ~ 50 g·L^-1的水溶液中电沉积可以得到中空馒头状和开口碗状结构的铜薄膜. 利用激光刻蚀模板,在离子液体1-丁基-3-甲基咪唑三氟甲磺酸盐([BMI][TfO]) - 30 Vol%丙醇混合电解质中电沉积CIGS薄膜,研究了沉积电势、沉积时间对薄膜形貌的影响. SEM观察发现,在沉积电势为-1.8 V,沉积时间为1.5 h条件下电沉积可以得到近似柱状的簇状花束样的CIGS薄膜, 电沉积铜后再进一步电沉积CIGS,得到了均匀有序的鼓包柱状结构的Cu/CIGS复合薄膜. 用恒电势方波法对制备的薄膜真实表面积进行测试,计算结果表明,与无模板电沉积制备的CIGS薄膜相比,激光刻蚀模板法制备的Cu/CIGS复合薄膜的表面积提高了约8倍.     

冬瓜皮表面白霜的超疏水性研究

冬瓜是一种常见的蔬菜,大部分品种成熟时表面覆盖一层类似于"白霜"的粉末。本文使用扫描电镜、接触角测量仪、傅立叶变换红外光谱、X射线衍射仪等设备对冬瓜皮表面白霜的浸润性、结构形貌及其组成进行了研究,证实了冬瓜皮表面白霜的超疏水特性,水滴在其表面的接触角高达154.8±3.5°,且滚动角小于5°。研究表明,冬瓜皮表面的白霜呈现微纳米多级拓扑结构,主要由长链脂肪酸、长链烷烃酯类组成,这种微纳米拓扑结构和化学组成的协同作用决定了冬瓜皮表面的超疏水性。本工作可为进一步了解、设计此类结构材料提供数据积累。     

Influence of substrate nature and growth conditions on the morphology of thin DMOAP films

We report some preliminary results on the morphology of thin N,N -dimethyl- n -octadecyl-3-aminopropyltrimethoxysilyl chloride (DMOAP) films. When deposited on a glass substrate, DMOAP forms a mono- or multi-layer structure parallel to the substrate. The surface topography of the film is probed by atomic force microscopy. In general, the free surface of such a film is not flat and smooth. Islands and holes are formed on the free surface of the films when a sufficiently flat substrate is used. The thin film surface topography depends strongly on the nature of the bare substrate, the curing conditions, and the immersion time of the substrate in the DMOAP solution. The film is always rougher than the bare substrate used. Annealing roughens the surface of the alkoxysilane thin films deposited on a glass substrate. For films on glass plates covered with an indium tin oxide layer, annealing has minor effects. The surface topography affects the microstructure of homeotropic smectic samples.     

Effects of UV irradiation on tribological properties of nano‐TiO2 thin films

One‐layer and two‐layer nano‐TiO₂ thin films were prepared on the surface of common glass by sol–gel processing. Water contact angle, surface morphology, tribological properties of the films before and after ultraviolet (UV) irradiation were investigated using DSA100 drop shape analyzer, scanning probe microscopy (SPM), SEM and universal micro‐materials tester (second generation) (UMT‐2MT) friction and wear tester, respectively. The stored films markedly resumed their hydrophilicity after UV irradiation. But UV irradiation worsened tribological properties of the films. After the film was irradiated by UV, the friction coefficient between the film and GCr15 steel ball increased about 10–50% and its wear life shortened about 20–90%. Abrasive wear, brittle break and adherence wear are the failure mechanisms of nano‐TiO₂ thin films. It was believed that UV irradiation increased surface energy of the film and then aggravated adherence wear of the film at initial stage of friction process leading to severe brittle fracture and abrasive wear. Copyright © 2009 John Wiley & Sons, Ltd.     

Facile synthesis of monodisperse microspheres and gigantic hollow shells of mesoporous silica in mixed water-ethanol solvents

Mesoporous silica materials with a variety of morphologies, such as monodisperse microspheres, gigantic hollow structures comprising a thin shell with a hole, and gigantic hollow structures consisting of an outer thin shell and an inner layer composed of many small spheres, have been readily synthesized in mixed water-ethanol solvents at room temperature using cetyltrimethylammonium bromide (CTAB) as the template. The obtained mesoporous silica generally shows a disordered mesostructure with typical average pore sizes ranging from 3.1 to 3.8 nm. The effects of the water-to-ethanol volume ratio (r), the volume content of tetraethyl orthosilicate TEOS (x), and the CTAB concentration in the solution on the final morphology of the mesoporous silica products have been investigated. The growth process of gigantic hollow shells of mesoporous silica through templating emulsion droplets of TEOS in mixed water-ethanol solution has been monitored directly with optical microscopy. Generally, the morphology of mesoporous silica can be regulated from microspheres through gigantic hollow structures composed of small spheres to gigantic hollow structures with a thin shell by increasing the water-to-ethanol volume ratio, increasing the TEOS volume content, or decreasing the CTAB concentration. A plausible mechanism for the morphological regulation of mesoporous silica by adjusting various experimental parameters has been put forward by considering the existing state of the unhydrolyzed and partially hydrolyzed TEOS in the synthesis system.     

Influence of substrate nature and growth conditions on the morphology of thin DMOAP films

We report some preliminary results on the morphology of thin N,N -dimethyl-n-octadecyl-3-aminopropyltrimethoxysilyl chloride (DMOAP) films. When deposited on a glass substrate, DMOAP forms a mono- or multi-layer structure parallel to the substrate. The surface topography of the film is probed by atomic force microscopy. In general, the free surface of such a film is not flat and smooth. Islands and holes are formed on the free surface of the films when a sufficiently flat substrate is used. The thin film surface topography depends strongly on the nature of the bare substrate, the curing conditions, and the immersion time of the substrate in the DMOAP solution. The film is always rougher than the bare substrate used. Annealing roughens the surface of the alkoxysilane thin films deposited on a glass substrate. For films on glass plates covered with an indium tin oxide layer, annealing has minor effects. The surface topography affects the microstructure of homeotropic smectic samples.     

Photocontrollable water permeation on the micro/nanoscale hierarchical structured ZnO mesh films

Most research of responsive surfaces mainly focus on the wettability transition on different solid substrate surfaces, but the dynamic properties of the micro/nanostructure-enhanced responsive wettability on microscale pore arrays are lacking and still remain a challenge. Here we report the photocontrollable water permeation on micro/nanoscale hierarchical structured ZnO-coated stainless steel mesh films. Especially, for aligned ZnO nanorod array-coated stainless steel mesh film, the film shows good water permeability under irradiation, while it is impermeable to water after dark storage. A detailed investigation indicates that the special nanostructure and the appropriate size of the microscale mesh pores play a crucial role in the excellent controllability over water permeation. The excellent controllability of water permeation on this film is promising in various important applications such as filtration, microreactor, and micro/nano fluidic devices. This work may provide interesting insight into the design of novel functional devices that are relevant to surface wettability.     

Ordered Mesostructured Silica Films: Effect of Pore Surface on its Sensing Properties

An electrochemical resistive-type sensor device, with a mesoporous silica thin film as sensitive membrane, has been developed and characterised. The silica film has been obtained via evaporation-induced self-assembly (EISA) using a tri-block copolymer (Pluronic F-127) as templating agent. It has been deposited by dip-coating on a silicon substrate with metallic interdigitated electrodes. Fast, reversible and reproducible electrical responses to relative humidity changes have been observed for the sensor device. The conduction mechanism has been related to chemical properties, structural order and surface morphology of the porosity in the silica film, confirming the dependence on the film preparation method and overall the importance of calcination temperature.