TiO2纳米粒子膜的制备,表面态性质和光催化活性

在酸性和碱性条件下,用ＴｉＣｌ４水解法制备了ＴｉＯ２纳米粒子膜催化剂。采用原子力显微镜（ＡＦＭ）,Ｘ射线衍射（ＸＲＤ）,表面光电压谱（ＳＰＳ）和场诱导表面光电压谱（ＥＦＩＳＰＳ）测定了催化剂表面的微结构及能级结构。     

金纳米粒子在平整硅基表面上的组装

采用水相硅烷化方法,将３－氨基丙基－三甲氧基硅烷（ＡＰＳ）组装在湿化学法处理的单晶硅表面上。接触角、原子力显微镜（ＡＦＭ）、Ｘ射线光电子能谱（ＸＰＳ）表征结果显示得到了平整均匀的具有氨基表面的自组装膜。ＳＥＭ观察表明,１６ｎｍ的金纳米粒子可以在上述氨基表面上形成均匀的亚单层排布,得到了具有Ａｕ纳米粒子／ＡＰＳ／Ｓｉ形成的纳米复合结构,进一步的处理可以使金纳米粒子在表面上的排列由随机趋于有序化。     

XPS和AES研究不锈钢上金色钼酸盐转化膜

用阴极电沉积法从钼酸盐溶液中取获得了金黄色的不锈钢转化膜，该膜具有良好的热稳定性和耐蚀性，ＸＰＳ和ＡＥＳ分析表明，膜厚约为６６３Ａ。膜的表面钼以Ｍｏ（Ⅵ）与Ｍｏ（Ⅳ）共存。从ＡＥＳ深度剥蚀曲线的组成恒定区求得膜的组成为：Ｏ５１．６％，Ｍｏ２８．５％，Ｐ１３．７％和Ｆｅ６．２％。循环伏安的氧化峰也证明膜内存在Ｍｏ（Ⅳ）。     

不锈钢上紫红色钼酸盐转化膜的研究

用阴极电沉积法从钼酸盐和磷酸盐混合溶液中获得了紫红色不锈钢转化膜，该膜具有良好的热稳定性。ＸＰＳ和ＡＥＳ分析表明，膜厚约９４．４ｎｍ。钼在膜表面以Ｍｏ（Ⅵ）存在，在膜内则以Ｍｏ（Ⅵ）和Ｍｏ（Ⅳ）共存。从ＡＥＳ深度剥蚀曲线的组成恒定区求得膜的组成为：Ｏ５４．８％，Ｍｏ３０．５％，Ｐ１１．２％和Ｆｅ３．５％，循环伏安的氧化峰也证明膜内存在Ｍｏ（Ⅳ）。     

聚甲基丙烯酸甲酯单分子膜的原子力学显微镜研究

报道了利用原子力显微镜（ＡＦＭ）技术对聚甲基丙烯酸甲酯（ＰＭＭＡ）单分子膜进行分子结构水平的观察研究．由ＡＰＭ图像中得到的ＰＭＭＡ单体所占面积与用π－Ａ曲线中换算出液面上ＰＭＭＡＬａｕｇｍｕｉｒ膜中单体的面积符合得很好．从ＡＦＭ图像中可见ＰＭＭＡＬＢ膜中ＰＭＭＡ的线型碳链是与档板（ｂａｒｒｉｅｒ）平行的紧密排列，与ＬＢ提膜方向相垂直．并由此对ＰＭＭＡＬＢ膜的形成过程进行分析．此外，还观察到了在Ｓｉ基底上ＰＭＭＡ直链的卷绕伸直排列形态，初步分析了其形成原因．     

InGaAsP／InP异质结构材料组分,结构的准确测定与综合分析

采用Ｘ射线光电子能谱（ＸＰＳ）对ＩｎＧａＡｓＰ／ＩｎＰ异质结构金属有机化学蒸发沉积（ＭＯＣＶＤ）外延晶片作了表面元素组分定性、定量和深度分布分析。将其组分定量数据代入带隙经验公式，发现带隙的计算与用光压谱（ＰＶＳ）实验值十分吻合；但是代入晶体常数经验计算公式计算得到的失配率与由Ｘ射线双晶衍射（ＤＣＤ）测定的失配率却有明显差别。抽检的两个外延晶片的ＸＰＳ元素分析和元素的深度分布分析，以对比的方式展示两者元素的组成、化学状态在其表面和沿着深度方向的变化及其差异，由此得到的有关片子质量的正确判断，有力地证明了ＸＰＳ是研究ＭＯＣＶＤ外延膜材料的得力工具。     

不锈钢上黑色钼酸盐转化膜的研究

用阴极电沉积法从钼酸盐和磷酸盐温和溶液中获得了黑色的不锈钢转化膜，该膜具有良好的热稳定性。电子能谱（ＸＰＳ和ＡＥＳ）分析表明，膜厚约为８２０ｎｍ，膜的表面钼以Ｍｏ（Ⅵ）存在，而在膜内则以Ｍｏ（Ⅵ）与Ｍｏ（Ⅳ）共存。从ＡＥＳ深度剥蚀曲线的组成恒定区求得膜的组成为：Ｏ５０．９％，Ｍｏ２９．４％，Ｐ１２．６％和Ｆｅ７．１％。循环伏安的氧化峰也证明膜内存在Ｍｏ（Ⅳ）。     

低能量链端对聚苯乙烯薄膜铺展和润湿行为的影响

通过低能量功能端基的表面富集作用,研究了聚苯乙烯（ＰＳ）薄膜在聚甲基丙烯酸甲酯（ＰＭＭＡ）表面上的铺展和润湿动力学．用光学显微镜跟踪了ＰＳ薄膜的润湿行为,并对高分子熔体膜中非连续部分尺寸的增大速率进行了测定．分别用ＸＰＳ和ＡＦＭ对ＰＳ薄膜的表面组成和ＰＳ液滴的平衡接触角进行了测定．发现具有低表面能的氟碳端基在薄膜表面富集使ＰＳ薄膜的表面张力下降,并使ＰＳ液滴在ＰＭＭＡ表面上的平衡接触角减小,从而使高分子熔体膜中非连续部分尺寸的增长速率下降,得到了与液液界面铺展和润湿理论一致的实验结果．     

固相配位化学反应研究：LXVII.金属铜表面M—S（M=Mo,W）簇合物的组成

采用ＦＴＩＲ、ＸＰＳ和ＡＥＳ研究了金属铜表面Ｍ－Ｓ（Ｍ＝Ｍｏ，Ｗ）簇合物膜。结果表明，Ｍｏ（Ｗ）Ｓ＾２－４与铜表面的Ｃｕ２Ｏ反应，形成了Ｍｏ（Ｗ）－Ｓ－Ｃｕ键。簇合物膜由Ｍｏ（Ｗ），Ｓ，Ｃｕ，Ｏ元素组成，分别呈＋６、－２、＋１、－２价，膜为多分子层结构并保持，ＭｏＳ４或ＷＳ２单元，膜表面只有Ｃｕ，Ｏ而不存在Ｍｏ（Ｗ），Ｓ，膜层厚度与反应时间有关，时间越长，膜越厚，膜为多组分的复杂体系，其颜色是各组     

用原子力显微镜研究磷脂酸Langmuir—Blodgett双层膜中超…

用原子力显微镜研究了二棕榈酰磷脂酸（ＤＰＰＡ）双层ＬＢ膜的分子排列结构，发现ＤＰＰＡ双层膜的分子排列具有长程的位置和取向有序，为有序大方结构，同时，在ＤＰＰＡ双层膜的极性区磷酸基团间存在局域超分子结构。     

酞菁铜阴阳离子分子沉积(MD)膜润湿性研究

酞菁及其衍生物等大环平面分子具有良好的化学稳定性和优异的光电性能 [1,2 ] ,利用酞菁进行模拟生物光合作用的研究 ,以期实现新的光电转换技术 ,近年来已引起人们的广泛重视[3～ 5] .分子沉积(MD)超薄膜[6～ 8] 是以阴阳离子间静电相互作用为成膜驱动力 ,通过相反离子体系的单层交替沉积制备的层状有序超薄膜 .分子沉积技术广泛应用在固体表面改性和生物传感技术等领域 ,沉积分子的物理化学性质是影响其应用的主要因素 .本文通过紫外 -可见光谱跟踪了酞菁铜阴阳离子 MD膜的均匀沉积 ,并根据酞菁 MD膜表面接触角的变化 ,探讨分子端基的…     

聚(ε-己内酯)薄膜结晶形貌及分子取向研究

用匀胶机通过溶液铸膜方法在硅片和铝箔基板上分别制备具有不同厚度的聚(ε-己内酯)(PCL)薄膜. 通过原子力显微镜(AFM)和偏光衰减全反射傅里叶红外光谱(ATR-FTIR)对薄膜中PCL的结晶形貌、 片晶生长方式及分子链取向进行了研究. AFM结果表明, 在200 nm或更厚的薄膜中, PCL主要以侧立(edge-on)片晶的方式生长; 对于厚度小于200 nm的薄膜, PCL片晶更倾向于以平躺(flat-on)的方式生长. 这种片晶生长方式的改变在硅片和铝箔基板上都表现出同样的倾向. 此外, 在15 nm或更薄的薄膜中, PCL结晶由通常的球晶结构变为树枝状晶体. 偏光ATR-FTIR结果表明, 当膜厚小于200 nm时, 薄膜结晶中PCL分子链沿垂直于基板表面方向取向, 并且膜越薄, 取向程度越高, 与AFM的观测结果一致.     

预沉积Ge对Si(111)衬底上SSMBE外延生长SiC薄膜的影响

利用固源分子束外延(SSMBE)生长技术, 在Si(111)衬底上预沉积不同厚度(0、0.2、1 nm)Ge, 在衬底温度900 ℃, 生长SiC单晶薄膜. 利用反射式高能电子衍射仪(RHEED)、原子力显微镜(AFM)和傅立叶变换红外光谱(FTIR)等实验技术, 对生长的样品进行了研究. 结果表明, 预沉积少量Ge(0.2 nm)的样品, SiC薄膜表面没有孔洞存在, AFM显示表面比较平整, 粗糙度比较小, FTIR结果表明薄膜内应力比较小. 这说明少量Ge的预沉积抑制了孔洞的形成, 避免衬底Si扩散, 因而SiC薄膜的质量比较好. 没有预沉积Ge的薄膜, 结晶质量比较差, SiC薄膜表面有孔洞且有Si存在. 然而预沉积过量Ge (1 nm) 的样品, 由于Ge的岛状生长,导致生长的SiC表面粗糙度变大, 结晶质量变差, 甚至导致多晶产生.     

LB技术制备FePt纳米粒子单层膜

FePt纳米粒子由于具有高的矫顽力而成为高密度垂直磁记录材料的研究热点之一,均匀有序排布的FePt纳米粒子薄膜将有利于提高磁记录介质的记录密度,因此,如何使FePt纳米颗粒均匀有序地排布是当前需要解决的关键问题之一,很多研究小组利用磁控溅射、自组装和电沉积等方法对FePt纳米颗粒的均匀分布进行了详细的研究,     

Preparation and Characterization of Ag2 O/Organicsilicone Self-assemblied Composite Film

The composite film of nanometer AgO2/silane coupling reagent aminopropyltriethoxy-silane (CH3O)3Si(CH2)3NH2was prepared on single-crystal silicon by the self-assembly of silane on the hydroxylated substrate followed with the deposition of nanometer AgO2 on the silane SAMs from an aqueous Ag2O gel. The resultant composite film was characterized by means of X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The contact angles of distilled water on the silane SAMs and the composite film were measured to compare the surface states. The experiment shows that the nanometer Ag2O can be easily incorporated in the silane SAMs and lead to changed surface state of the composite film. Nanometer Ag2O crystallites in a size of about 20 nm distribute quite uniformly in the composite film. It was anticipated that the composite film might find application to the protection of single-crystal Si substrate in MEMS devices and also propose a novel single electron device structure based on nanoscale Ag2O colloidal particles.     

A Surface Masking Technique for the Determination of Plasma Polymer Film Thickness by AFM

A method for the determination of coating film thicknesses at nanometer resolution based on surface masking and atomic force microscopy (AFM) is described. A polymeric mask is used to cover part of a substrate during the deposition of thin polymeric coatings by plasma polymerization, allowing the production of well defined polymer steps of heights of a few tens of nanometers. Tapping mode AFM has been employed to analyze the topography of these steps at high resolution. This method has also allowed accurate measurement of the kinetics of the deposition of plasma polymer films over a range of exposure times. XPS analysis of different substrate surfaces following mask removal found barely detectable residues, suggesting that the underlying surface chemistry remains unchanged, and accessible for further modification. In combination with quartz crystal microgravimetry, the method has been applied to the measurement of the density of plasma polymer coatings in the thickness range 4–50 nm.     

Comparative characterisation by atomic force microscopy and ellipsometry of soft and solid thin films

Ellipsometry and atomic force microscopy (AFM) were used to study the film thickness and the surface roughness of both ‘soft’ and solid thin films. ‘Soft’ polymer thin films of polystyrene and poly(styrene–ethylene/butylene–styrene) block copolymer were prepared by spin‐coating onto planar silicon wafers. Ellipsometric parameters were fitted by the Cauchy approach using a two‐layer model with planar boundaries between the layers. The smooth surfaces of the prepared polymer films were confirmed by AFM. There is good agreement between AFM and ellipsometry in the 80–130 nm thickness range. Semiconductor surfaces (Si) obtained by anisotropic chemical etching were investigated as an example of a randomly rough surface. To define roughness parameters by ellipsometry, the top rough layers were treated as thin films according to the Bruggeman effective medium approximation (BEMA). Surface roughness values measured by AFM and ellipsometry show the same tendency of increasing roughness with increased etching time, although AFM results depend on the used window size. The combined use of both methods appears to offer the most comprehensive route to quantitative surface roughness characterisation of solid films. Copyright © 2007 John Wiley & Sons, Ltd.     

Preferential adsorption of amino-terminated silane in a binary mixed self-assembled monolayer

The composition and structure of a binary mixed self-assembled monolayer (SAM) of 3-aminopropyltriethoxysilane (APS, NH(2)(CH(2))(3)Si(OCH(2)CH(3))(3)) and octadecyltrimethoxysilane (ODS, CH(3)(CH(2))(17)Si(OCH(3))(3)) on a silicon oxide surface have been characterized by water contact-angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and sum frequency generation (SFG) vibrational spectroscopy. XPS demonstrated that APS in the mixed SAM is significantly enriched in comparison to that in solution, indicating the preferential adsorption of APS during the SAM formation. AFM observations showed that the mixed SAM becomes rougher. SFG revealed that the coadsorption of APS induced a conformation disordering in the ODS molecules present in the mixed SAM. The surface enrichment of APS has been explained in terms of differences in the surface adsorption rates of the two components as well as in the self-congregation states of APS molecules in the bulk solution. Furthermore, the structure of the water molecules on the mixed SAM surface in contact with the aqueous solutions at different pH's has also been studied. The results indicate that the mixed-SAM modified surface is positively charged at pH < 5 and negatively charged at pH > 7.     

聚电解质PSS/PDDA分子沉积膜表面性能研究

PSS PDDAMD膜紫外 可见吸光度与层数呈线性关系 ,其延长线基本为零证实了是一单分子层层状沉积过程 ;利用接触角测量仪跟踪MD膜沉积过程 ,其结果表明 ,层数较少时PSS PDDAMD膜表面润湿性呈“奇 偶”性规律变化 ,层数较多时规律性不明显 ,这说明聚电解质MD膜结构缺陷随着层数的增加有增大趋势 ;通过对原子力显微镜 (AFM)测定结果的分析 ,进一步证实了多层PSS PDDAMD膜存在结构缺陷 .     

Piezoelectricity of ZnO Films Prepared by Sol-Gel Method

"ZnO piezoelectric thin films were prepared on crystal substrate Si(111) by sol-gel technology, then characterized by scanning electron microscopy, X-ray diffraction and atomic force microscopy (AFM). The ZnO films characterized by X-ray diffraction are highly oriented in (002) direction with the growing of the film thickness. The morphologies, roughness and grain size of ZnO film investigated by AFM show that roughness and grain size of ZnO piezoelectric films decrease with the increase of the film thickness. The roughness dimension is 2.188-0.914 nm. The piezoelectric coeocient d33 was investigated with a piezo-response force microscope (PFM). The results show that the piezoelectric coeocient increases with the increase of thickness and (002) orientation. When the force reference is close to surface roughness of the films, the piezoelectric coefficient measured is inaccurate and fluctuates in a large range, but when the force reference is big, the piezoelectric coeocient d33 changes little and ultimately keeps constant at a low frequency."