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Well-ordered nanoparticle arrays are attractive platforms for a variety of analytical applications, but the fabrication of such arrays is generally challenging. Here, it is demonstrated that scanning electrochemical cell microscopy (SECCM) can be used as a powerful, instantly reconfigurable tool for the fabrication of ordered nanoparticle arrays. Using SECCM, Ag nanoparticle arrays were straightforwardly fabricated via electrodeposition at the interface between a substrate electrode and an electrolyte-filled pipet. By dynamically monitoring the currents flowing in an SECCM cell, individual nucleation and growth events could be detected and controlled to yield individual nanoparticles of controlled size. Characterization of the resulting arrays demonstrate that this SECCM-based approach enables spatial control of nanoparticle location comparable with the terminal diameter of the pipet employed and straightforward control over the volume of material deposited at each site within an array. These results provide further evidence for the utility of probe-based electrochemical techniques such as SECCM as tools for surface modification in addition to analysis.
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This content will become publicly available on January 23, 2026
Tuning Fork Scanning Electrochemical Cell Microscopy for Resolving Morphological and Redox Properties of Single Ag Nanowires
We report a Tuning Fork Scanning Electrochemical Cell Microscopy (TF-SECCM) technique for providing morphological and electrochemical information of single redox-active entities. This new operation configuration of SECCM utilizes an electrolyte-filled nanopipette tip mounted onto a tuning fork force sensor to obtain a precise tip-sample distance control and surface morphological mapping. Redox activities of regions of interest can be investigated by scanning electrode potential by moving the nanopipette to any target regions while maintaining the constant force engagement of the tip with the sample. Using silver nanowires (Ag NWs) as a model system due to their extensive utilization in energy and sensing devices, TF-SECCM provides not only the topography of single Ag NWs but also their distinctive redox activities and catalytic hydrogen evolution reaction (HER) activities and electrolyte anion adsorption/desorption features in contrast to NW bundles and supporting substrate (e.g., indium tin oxide).
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- Award ID(s):
- 2113505
- PAR ID:
- 10569482
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry Letters
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 1948-7185
- Page Range / eLocation ID:
- 818 to 825
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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