Effect of thickness on structures of ultrathin diamond-like carbon films

Diamond-like carbon (DLC) films with different thickness were deposited by filtered cathode vacuum arc (FCVA). Vis-Raman and spectroscopic ellipsometry were employed to analyze the structure of DLC films. The wavelength of Vis-Raman is 514.5 nm. Experimental results show that structures of DLC films are affected by film thicknesses. When the film thickness increases from 2 to 30 nm, the G-peak position (G-pos) shifts to higher wavelength, the intensity ratio I_D/I_G and the extinction coefficient Ks decrease. It is indicated that the content of sp3 bond increases with film thickness. However, when the film thickness increases from 30 nm to 50 nm, I_D/I_G and Ks increase. The content of sp³ bonds decreases with film thickness.     

巨轮型多金属氧酸盐纳米超薄多层膜的制备

首次将巨轮型纳米多孔多金属氧酸盐Na₁₅［Mo^VI₁₂₆Mo^V₂₈O₄₆₂H₁₄(H₂O)₇₀］_0.5［Mo^VI₁₂₄Mo^V₂₈O₄₅₇H₁₄(H₂O)₆₈］_0.5·ca.400H₂O通过层层自组装的方法,与聚乙烯基亚胺（PEI）通过静电作用自组装形成纳米超薄多层膜。该膜的制备过程通过紫外可见光谱进行监测,巨轮型纳米多孔多金属氧酸盐的特征吸收峰的吸收值随着层数的增加呈线性增长关系,表明在纳米超薄多层膜的组装过程中巨轮型多金属氧酸盐的结构没有被破坏,自组装成膜的过程是一个层层均一、反复生长的过程,每层吸附循环沉积的聚电解质和多金属氧酸盐的量相等。对纳米超薄多层膜的偏振紫外光谱的研究表明巨轮型纳米多孔多金属氧酸盐分子在纳米超薄膜中不是杂乱无章随意排列堆积的,而是在带高负电荷的巨轮型纳米多孔多金属氧酸阴离子间存在的静电排斥作用下彼此平行倾斜在基片表面并且与基片表面成一定的取向角从而减低整个体系的能量达到最稳定状态。     

CoAPO-5沸石晶体的合成及表征

利用水热方法,生长出了不同掺Co2+摩尔比的AlPO4-5沸石晶体(CoAPO-5)。X射线粉末衍射(XRD)和傅立叶红外吸收(FTIR)分析了晶体的结构,结果表明,Co2+离子的引入并没有显著改变AlPO4-5晶体的晶格结构;光学显微镜和扫描电子显微镜(SEM)观测了CoAPO-5晶体的光学质量和表观尺寸,结果显示,合成出的晶体形貌完整、透明,尺寸达到45 mμ×45μm×300μm;X射线荧光分析(XRF)测试了CoA-PO-5晶体的化学成分,结果表明,当Co2+离子进入AlPO4-5晶格中取代了Al3+离子,使晶体晶格带负电性,且由此导致Brφnsted酸位的产生。     

聚苯胺修饰电极的制备与形貌、阻抗表征

运用循环伏安(CV)法制取聚苯胺,结合扫描电子显微镜(SEM)、阻抗谱(EIS)等手段,对聚苯胺的表面形貌及其特征进行研究,并建立了聚苯胺覆盖Pt电极的阻抗模型.实验表明,随着循环次数的增加,聚苯胺膜厚增加,而且所制得的聚苯胺膜呈现多孔、疏松的特征,符合其作为基体材料的特点.     

Characterization of ultrathin SiO 2/Si interface grown by low temperature plasma oxidation

Ultrathin SiO 2 layers on Si (100) wafers were prepared by plasma oxidation at a low temperature (250℃). The analyses of X-ray photoelectron spectroscopy (XPS) and TEM reveal that the chemical composition of the oxide layer is stoichiometric SiO 2 and the SiO 2/Si interface is abrupt. The thickness of the ultrathin oxide layer obtained from XPS, capacitance-voltage (C-V) and ellipsometry measurements indicate a nonlinear time dependence. The high frequency C-V characterization of MOS structure shows that the fixed charge density in SiO 2 film is about 10 11 cm -2 . It is also shown that the strength of breakdown electrical field of SiO 2 film with 6 nm thickness is of the order of 10 6 Vcm -1 . These properties of the ultrathin SiO 2 layer ensure its application in silicon quantum devices.     

超薄润滑膜界面滑移现象的分子动力学研究

为研究超薄润滑膜的流变和滑移特性 ,采用了分子动力学模拟方法。模拟系统由 2个固体壁面和介于壁面间的润滑剂分子构成 ,分子模型为正癸烷。结果表明 :薄膜中粒子密度沿膜厚方向呈周期性变化 ,存在某种有序结构 ;薄膜中润滑剂分子的平均速度仍大体呈线性分布 ,但在固液界面和液体层间可以观察到滑移现象 ;壁面滑移率随着剪切率的增加而上升 ,并在高剪切率区迅速增大 ;分子级薄膜中一个重要现象是滑移可能在较低的剪切率下发生 ;薄膜中润滑剂经历着向固态转化的相变过程 ,低剪切率下的滑移率可作为衡量薄膜固化程度的定量判据     

Study on Electrical Property of Polyaniline Composite Film

Polyaniline was synthesized by chemically oxidative poly-merization.By means of infrared spectroscopy,the dif-ference between its intrinsic state structure and its dopedstate structure was determined for researching the rela-tionship between macromolecular structure and conduc-tive property before and after doping.The morphologyof solution-processed polyblends with the electricallyconductive polyaniline-camphor sulfonic acid complex(PAn-CSA)was investigated by using scanning electronmicroscopy.The conductive percolation threshold of thecomposite films is about 2.8%.     

邻苯二胺超薄膜修饰电极上碘的电化学行为的研究

在自制石墨-环氧树脂固态电极上，于不完全的单体氧化电位下，以循环伏安法制备邻苯二胺超薄（UT-PPD），得到两对可逆氧化还原峰，分别归属于两种结构的电聚合产物．实验研究了碘离子在该膜中的电化学行为，得到掺杂反应的一级反应速率常数0．062s^-1和离子缔合常数7．11．该UT-PPD膜对碘离子氧化反应具有很高的催化能力，单位吸附量的聚合膜产生的催化效率为普通PPD膜的8．8倍．     

BCN薄膜的结构及其内应力研究

用射频反应溅射法制备出BCN薄膜。X射线衍射和傅立叶红外吸收光谱量发现样品的组成原子之间实现了原子级化合，样品与Si衬底之间存在较大的应力。样品剥落后，应力的消除使红外吸收峰位向低波数移动。实际还发现，衬底材料对样品中的压应力影响很大，压应力的释放与衬底密切相关：在硅衬底上呈枫叶状隆起，在石英衬底上样品呈周期性的拆线状隆起。     

生物酶催化聚乙烯膜接枝的改性方法

目的 研究以辣根过氧化物酶（HRP）为催化剂，邻甲氧基酚为底物，H2O2为氧化剂的自由基引发体系，高密度聚乙烯膜（HDPE）接枝丙烯酰胺的反应过程。考察催化反应各参数对HDPE膜亲水性和染色性能的影响。方法用SEM，UV-Vis分析聚合物膜的组成和表面结构。测定改性HDPE膜的接触角和染色后膜的UV-vis吸光度，分析溶剂浓度对改性效果的影响。结果最佳处理条件是反应时间为1．5h，H2O2的浓度为0．03％（质量分数），邻甲氧基酚的浓度为0．5％（质量分数），反应液中丙酮的最佳浓度为30％（体积分数）。结论HRP催化接枝处理HDPE膜明显改善了其亲水性和染色性能。     

射频磁控溅射法LiNbO3薄膜的制备及其影响因素研究

采用射频磁控溅射法在Si(111)和Si(100)上制备LiNbO3薄膜.通过XRD技术探讨了硅基片取向和所制备的薄膜的取向之间的联系,研究了不同靶材对薄膜的影响,讨论了热处理温度、工艺和所制备的薄膜取向的关系.报道了在Si(111)基片上制备高c轴取向的LiNbO压电薄膜的制备方法.     

ESA/AMPS共聚物的合成、表征及性能研究

描述了共聚物ESA/AMPS的合成。红外光谱法和元素分析法表征了共聚物的结构。考察了其阻垢分散性能,并利用扫描电镜对形成的垢样CaCO3形貌和晶形进行了观察和分析。结果表明,共聚物具有良好的阻垢分散性能,ESA/AMPS共聚物对垢样晶形有扭曲的作用。     

Epitaxial growth of ultrathin ZrO2（111） films on Pt（111）

Ordered epitaxial ZrO2 films were grown on Pt(111) and characterized by low energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES) and X-ray photoelectron spectroscopy (XPS). The films were prepared by vapor deposition of zirconium in an O2 atmosphere followed by annealing under ultra high vacuum. At low coverages, the films grew as discontinuous two-dimentional islands with ordered structures. The size and structure of these islands were dependent on the coverage of Zr...