Simple and clear evidence for positive feedback limitation by bipolar behavior during scanning electrochemical microscopy of unbiased conductors.

On the basis of an experimentally validated simple theoretical model, it is demonstrated unambiguously that when an unbiased conductor is probed by a scanning electrochemical tip (scanning electrochemical microscopy, SECM), it performs as a bipolar electrode. Though already envisioned in most recent SECM theories, this phenomenon is generally overlooked in SECM experimental investigations. However, as is shown here, this may alter significantly positive feedback measurements when the probed conductor is not much larger than the tip.

[1]  B. Mizaikoff,et al.  Numerical simulation of scanning electrochemical microscopy experiments with frame-shaped integrated atomic force microscopy--SECM probes using the boundary element method. , 2005, Analytical chemistry.

[2]  Li Zhang,et al.  Microfabrication of a Diffractive Microlens Array on n‐GaAs by an Efficient Electrochemical Method , 2007 .

[3]  C. Lefrou,et al.  New analytical approximation of feedback approach curves with a microdisk SECM tip and irreversible kinetic reaction at the substrate , 2008 .

[4]  J. A. Jankowski,et al.  Analysis of diffusional broadening of vesicular packets of catecholamines released from biological cells during exocytosis. , 1992, Analytical chemistry.

[5]  C. Lefrou.  A unified new analytical approximation for positive feedback currents with a microdisk SECM tip , 2006 .

[6]  Wolfgang Schuhmann,et al.  Imaging immobilised ssDNA and detecting DNA hybridisation by means of the repelling mode of scanning electrochemical microscopy (SECM). , 2004, Biosensors & bioelectronics.

[7]  S. Daniele,et al.  Ex Situ Scanning Electrochemical Microscopy (SECM) Investigation of Bismuth- and Bismuth/Lead Alloy Film-Modified Gold Electrodes in Alkaline Medium , 2010 .

[8]  H. Girault,et al.  Oxygen reduction catalyzed by a fluorinated tetraphenylporphyrin free base at liquid/liquid interfaces. , 2010, Journal of the American Chemical Society.

[9]  R. Murray,et al.  SECM Measurement of the Fast Electron Transfer Dynamics between Au381+ Nanoparticles and Aqueous Redox Species at a Liquid/Liquid Interface , 2004 .

[10]  C. Lefrou,et al.  A unified new analytical approximation for negative feedback currents with a microdisk SECM tip , 2007 .

[11]  S. Szunerits,et al.  The real meaning of Nernst's steady diffusion layer concept under non-forced hydrodynamic conditions. A simple model based on Levich's seminal view of convection , 2001 .

[12]  W. Schuhmann,et al.  4D shearforce-based constant-distance mode scanning electrochemical microscopy. , 2010, Analytical chemistry.

[13]  P. Unwin,et al.  Polyaniline Langmuir-Blodgett films: formation and properties. , 2009, Physical chemistry chemical physics : PCCP.

[14]  P. Hapiot,et al.  SECM investigations of immobilized porphyrins films. , 2010, Langmuir.

[15]  O. Guenat,et al.  Addressable Microelectrode Arrays: Characterization by Imaging with Scanning Electrochemical Microscopy , 2004 .

[16]  A. Bard,et al.  Scanning electrochemical microscopy. 12. Theory and experiment of the feedback mode with finite heterogeneous electron-transfer kinetics and arbitrary substrate size , 1992 .

[17]  A. Bard,et al.  Reaction of Various Reductants with Oxide Films on Pt Electrodes As Studied by the Surface Interrogation Mode of Scanning Electrochemical Microscopy (SI-SECM): Possible Validity of a Marcus Relationship , 2010 .

[18]  H. Xiong,et al.  Probing heterogeneous electron transfer at an unbiased conductor by scanning electrochemical microscopy in the feedback mode. , 2007, Analytical chemistry.

[19]  Eunkyoung Kim,et al.  Spatially resolved detection of a nanometer-scale gap by scanning electrochemical microscopy. , 2009, Analytical chemistry.

[20]  Christian Amatore,et al.  Electrochemical monitoring of single cell secretion: vesicular exocytosis and oxidative stress. , 2008, Chemical reviews.

[21]  M. Baldo,et al.  Characterization of metal-supported Al2O3 thin films by scanning electrochemical microscopy , 2010 .

[22]  M. Mirkin,et al.  Probing Ion Transfer at the Liquid/Liquid Interface by Scanning Electrochemical Microscopy (SECM) , 1998 .

[23]  Zhong-Qun Tian,et al.  Confined etchant layer technique for two-dimensional lithography at high resolution using electrochemical scanning tunnelling microscopy , 1992 .

[24]  François O. Laforge,et al.  Nanoelectrochemistry of mammalian cells , 2008, Proceedings of the National Academy of Sciences.

[25]  W. Schuhmann,et al.  Scanning electrochemical microscopy in neuroscience. , 2010, Annual review of analytical chemistry.

[26]  Christopher M.A. Brett,et al.  Electrochemistry: Principles, Methods, and Applications , 1993 .

[27]  Yukio Saito,et al.  A Theoretical Study on the Diffusion Current at the Stationary Electrodes of Circular and Narrow Band Types , 1968 .

[28]  N. Nioradze,et al.  Quasi-steady-state voltammetry of rapid electron transfer reactions at the macroscopic substrate of the scanning electrochemical microscope. , 2011, Analytical chemistry.

[29]  C. Lagrost,et al.  Charge Transfer between Electroactive Species Immobilized on Carbon Surfaces by Aryl Diazonium Reduction. SECM Investigations , 2010 .

[30]  Wolfgang Schuhmann,et al.  Single-cell microelectrochemistry. , 2007, Angewandte Chemie.

[31]  P. Unwin,et al.  Intermittent contact-scanning electrochemical microscopy (IC-SECM): a new approach for tip positioning and simultaneous imaging of interfacial topography and activity. , 2010, Analytical chemistry.

[32]  ARTIFICIAL NEURONS WITH LOGICAL PROPERTIES BASED ON PAIRED-BAND MICROELECTRODE ASSEMBLIES , 1999 .

[33]  A. Bard,et al.  Scanning Electrochemical Microscopy VII . Effect of Heterogeneous Electron‐Transfer Rate at the Substrate on the Tip Feedback Current , 1991 .

[34]  H. Shiku,et al.  Simultaneous noncontact topography and electrochemical imaging by SECM/SICM featuring ion current feedback regulation. , 2010, Journal of the American Chemical Society.

[35]  W. Schuhmann,et al.  Redox competition mode of scanning electrochemical microscopy (RC-SECM) for visualisation of local catalytic activity. , 2006, Physical chemistry chemical physics : PCCP.

[36]  Allen J. Bard,et al.  Rapid Screening of BiVO4-Based Photocatalysts by Scanning Electrochemical Microscopy (SECM) and Studies of Their Photoelectrochemical Properties , 2010 .

[37]  G. Wittstock,et al.  Investigation of Localized Catalytic and Electrocatalytic Processes and Corrosion Reactions with Scanning Electrochemical Microscopy (SECM) , 2008 .

[38]  T. Livache,et al.  New approach to writing and simultaneous reading of micropatterns: combining surface plasmon resonance imaging with scanning electrochemical microscopy (SECM). , 2004, Langmuir : the ACS journal of surfaces and colloids.

[39]  R. Crooks,et al.  Two-dimensional bipolar electrochemistry. , 2010, Journal of the American Chemical Society.

[40]  J. Heinze,et al.  SECM characterization of immobilised enzymes by self-assembled monolayers on titanium dioxide surfaces. , 2007, Bioelectrochemistry.

[41]  A. Bard,et al.  Kinetics of Heterogeneous Electron Transfer at Liquid/Liquid Interfaces As Studied by SECM , 2001 .