BROWSE

Related Researcher

Author's Photo

Shin, Heungjoo
Micro/Nano Integrated Systems (MNIS) Lab
Research Interests
  • Carbon-MEMS
  • Nanofabrication
  • Gas sensors
  • Biosensors
  • Electrochemical sensors
  • SPM

ITEM VIEW & DOWNLOAD

Frequency dependence of the electrochemical activity contrast in AC-scanning electrochemical microscopy and atomic force microscopy-AC-scanning electrochemical microscopy imaging

Cited 16 times inthomson ciCited 14 times inthomson ci
Title
Frequency dependence of the electrochemical activity contrast in AC-scanning electrochemical microscopy and atomic force microscopy-AC-scanning electrochemical microscopy imaging
Author
Eckhard, KathrinKranz, ChristineShin, HeungjooMizaikoff, BorisSchuhmann, Wolfgang
Keywords
IMPEDANCE SPECTROSCOPY; LOCALIZED CORROSION; SECM; MODE; DISTANCE; PROBES; RESOLUTION; ELECTRODE; SURFACES
Issue Date
2007-07
Publisher
AMER CHEMICAL SOC
Citation
ANALYTICAL CHEMISTRY, v.79, no.14, pp.5435 - 5438
Abstract
Alternating current mode scanning electrochemical microscopy (AC-SECM) enables local detection of electrochemical surface activity without any redox mediator present in solution. Z-approach curves toward the substrate result in a negative feedback curve of the ac signal for insulating samples. On conducting samples, however, the shape of the feedback curve was found to be dependent on the ac perturbation frequency. Approach curves over a wide range of frequencies were performed, and the results were applied to interpret laterally resolved frequency-dependent measurements obtained with combined atomic force microscopy-AC-SECM (AFM-AC-SECM). For the first time, this frequency dependence of the signal was utilized to fine-tune the electrochemical contrast in lateral imaging in AC-SECM. An array of gold microelectrodes embedded in silicon nitride displaying significant changes in electrochemical activity as well as in topography was investigated using a bifunctional AFM-SECM tip with an integrated recessed ring microelectrode. Due to the unique geometrical conditions the electrochemical contrast between the conducting gold spots and the insulating SixNy is reversed, crosses zero, and inverts as a function of the applied ac frequency.
URI
Go to Link
DOI
10.1021/ac070605e
ISSN
0003-2700
Appears in Collections:
MEN_Journal Papers
Files in This Item:
2-s2.0-34547182377.pdf Download

find_unist can give you direct access to the published full text of this article. (UNISTARs only)

Show full item record

qrcode

  • mendeley

    citeulike

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

MENU