Characterization of Nanopipet-Supported ITIES Tips for Scanning Electrochemical Microscopy of Single Solid-State Nanopores.
Characterization of Nanopipet-Supported ITIES Tips for Scanning Electrochemical Microscopy of Single Solid-State Nanopores.
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DOI：
10.1021/acs.analchem.7b02269
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发表时间：
2017-09-19
影响因子：
7.4
通讯作者：
Amemiya S
中科院分区：
文献类型：
--
作者：
Chen R;Balla RJ;Lima A;Amemiya S
纳米扫描电化学显微镜（SECM）是一种强大的扫描探针技术，可以对单个纳米尺寸物体的化学过程进行高分辨率成像。然而，它一直是一个具有挑战性的任务，定量地了解纳米SECM图像，这需要准确地表征纳米电极尖端的尺寸和几何形状。在此，我们通过使用两种不混溶的电解质溶液（ITIES）之间的纳米吸管支撑界面作为吸头，通过石英纳米吸管的透射电子显微镜（TEM）对单个固态纳米孔进行SECM成像来解决这一挑战。我们利用TEM的高分辨率来证明，激光提拉石英纳米移液管不仅可再现地产生~30 nm的极小尖端直径，而且还产生~5 nm的显著尖端粗糙度。纳米吸量管的尺寸和粗糙度可以通过优化电子束的强度以使没有金属涂层的石英纳米尖端不熔化或变形来可靠地确定。电化学，纳米ITIES支持的粗糙nanotip给更高的电流响应四丁基铵比预期的30 nm直径的磁盘尖端。球帽ITIES尖端的有限元模拟解释了高电流响应，并且还揭示了100 nm直径的Si 3 N4纳米孔的SECM图像沿尖端扫描的方向沿着放大。尽管如此，空间分辨率不会受到球帽尖端的显著影响，球帽尖端可以在更靠近基板的位置进行扫描。这一发现增强了突出尖端的实用性，其可以更容易地制造和小型化以促进纳米级SECM成像。
Nanoscale scanning electrochemical microscopy (SECM) is a powerful scanning probe technique that enables high-resolution imaging of chemical processes at single nanometer-sized objects. However, it has been a challenging task to quantitatively understand nanoscale SECM images, which requires to accurately characterize the size and geometry of nanoelectrode tips. Herein, we address this challenge through transmission electron microscopy (TEM) of quartz nanopipets for SECM imaging of single solid-state nanopores by using nanopipet-supported interfaces between two immiscible electrolyte solutions (ITIES) as tips. We take advantage of the high resolution of TEM to demonstrate that laser-pulled quartz nanopipets reproducibly yield not only an extremely small tip diameter of ~30 nm, but also a substantial tip roughness of ~5 nm. The size and roughness of a nanopipet can be reliably determined by optimizing the intensity of the electron beam not to melt or deform the quartz nanotip without metal coating. Electrochemically, the nanoscale ITIES supported by a rough nanotip gives higher amperometric responses to tetrabutylammonium than expected for a 30 nm-diameter disk tip. The finite element simulation of sphere-cap ITIES tips accounts for the high current responses and also reveals that the SECM images of 100 nm-diameter Si3N4 nanopores are enlarged along the direction of the tip scan. Nevertheless, spatial resolution is not significantly compromised by a sphere-cap tip, which can be scanned in closer proximity to the substrate. This finding augments the utility of a protruded tip, which can be fabricated and miniaturized more readily to facilitate nanoscale SECM imaging.
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用于扫描电化学显微镜的聚焦离子束式碳纳米电极。
影响因子：
3.9
作者：
Chen R;Hu K;Yu Y;Mirkin MV;Amemiya S
通讯作者：
Amemiya S
影响因子：
7.4
作者：
Cornut, Renaud;Bhasin, Amit;Lefrou, Christine
通讯作者：
Lefrou, Christine
影响因子：
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作者：
BARD, AJ;MIRKIN, MV;WIPF, DO
通讯作者：
WIPF, DO
影响因子：
7.4
作者：
Nioradze, Nikoloz;Chen, Ran;Kim, Jiyeon;Shen, Mei;Santhosh, Padmanabhan;Amemiya, Shigeru
通讯作者：
Amemiya, Shigeru
影响因子：
7.4
作者：
Kim, Jiyeon;Renault, Christophe;Bard, Allen J.
通讯作者：
Bard, Allen J.