高分辨率超低压扫描电镜直接观察介孔二氧化硅薄膜的最外表面,Langmuir

当前位置： X-MOL 学术 › Langmuir › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

高分辨率超低压扫描电镜直接观察介孔二氧化硅薄膜的最外表面
Langmuir ( IF 3.7 ) Pub Date : 2017-02-20 00:00:00 , DOI: 10.1021/acs.langmuir.6b04511
Maho Kobayashi ₁ , Kyoka Susuki ₁ , Haruo Otsuji ₂ , Yusuke Sakuda ₃ , Shunsuke Asahina ₃ , Naoki Kikuchi ₃ , Toshiyuki Kanazawa ₃ , Yoshiyuki Kuroda ₄ , Hiroaki Wada ₁ , Atsushi Shimojima ₁ , Kazuyuki Kuroda _{1,

2}

Affiliation

介孔二氧化硅薄膜的最外表面的性质对于确定其功能至关重要。获得有关膜表面上是否存在二氧化硅层以及中孔开度的信息对于表面中孔的应用是必不可少的。在这项研究中，使用具有减速光学系统的超低压高分辨率扫描电子显微镜（HR-SEM）观察了具有3维正交晶和2维六角形结构的介孔二氧化硅薄膜的最外表面。用NH ₄蚀刻前后的表面SEM图像F是在各种着陆电压下取得的。比较在不同条件下获得的图像，表明未蚀刻的中孔二氧化硅薄膜的最外表面涂覆有二氧化硅薄层。在超低着陆电压（即80 V）下拍摄的图像显示，表面二氧化硅层的存在与否取决于是否用NH ₄水溶液蚀刻了该膜F.在常规着陆电压（2 kV）下拍摄的图像中，可以看到蚀刻膜和未蚀刻膜的介孔结构。因此，超低着陆电压更适合分析最外表面。SEM观察结果提供了有关中孔二氧化硅薄膜表面的详细信息，例如开孔程度及其均质性。未刻蚀的二维六角形介孔二氧化硅薄膜的AFM图像显示，薄膜表面上的二氧化硅层的形状反映了圆柱形介孔顶表面的曲率。讨论了在各个着陆电压下拍摄的SEM图像，以及每个电压下的电子穿透范围。这项研究增加了我们对介孔二氧化硅薄膜表面的了解，

"点击查看英文标题和摘要"

Direct Observation of the Outermost Surfaces of Mesoporous Silica Thin Films by High Resolution Ultralow Voltage Scanning Electron Microscopy

The properties of the outermost surfaces of mesoporous silica thin films are critical in determining their functions. Obtaining information on the presence or absence of silica layers on the film surfaces and on the degree of mesopore opening is essential for applications of surface mesopores. In this study, the outermost surfaces of mesoporous silica thin films with 3-dimensional orthorhombic and 2-dimensional hexagonal structures were observed using ultralow voltage high resolution scanning electron microscopy (HR-SEM) with decelerating optics. SEM images of the surfaces before and after etching with NH₄F were taken at various landing voltages. Comparing the images taken under different conditions indicated that the outermost surfaces of the nonetched mesoporous silica thin films are coated with a thin layer of silica. The images taken at an ultralow landing voltage (i.e., 80 V) showed that the presence or absence of surface silica layers depends on whether the film was etched with an aqueous solution of NH₄F. The mesostructures of both the etched and nonetched films were visible in images taken at a conventional landing voltage (2 kV); hence, the ultralow landing voltage was more suitable for analyzing the outermost surfaces. The SEM observations provided detailed information about the surfaces of mesoporous silica thin films, such as the degree of pore opening and their homogeneities. AFM images of nonetched 2-dimensional hexagonal mesoporous silica thin films show that the shape of the silica layer on the surface of the films reflects the curvature of the top surface of the cylindrical mesochannels. SEM images taken at various landing voltages are discussed, with respect to the electron penetration range at each voltage. This study increases our understanding of the surfaces of mesoporous silica thin films, which may lead to potential applications utilizing the periodically arranged mesopores on these surfaces.

更新日期：2017-02-20

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南