Automatic Target Location Strategy-A Novel Approach in Scanning Electrochemical Microscopy

Abstract

In this article a recently constructed scanning electrochemical microscope with an original automatic target location facility is described and its operation is demonstrated on different targets. The measuring tip positioning device is based on stepper motor driven linear modules with 75 nm linear travel resolution. The home-built electronic unit and the Windows 95 compatible measuring and image-forming program furnish the microscope to operate in both amperometric and potentiometric modes. A novel, simplex algorithm based automatic target location program was developed to substitute the tedious and lengthy manual tip positioning. In this article different strategies are described and the most important results of this investigation are summarized.

Spatially resolved measurement of electrochemical activity and pH distributions in corrosion processes by scanning electrochemical microscopy using antimony microelectrode tips

“…A home-built SECM system was employed [17], using a 3D positioning device driven by precision step motors with 75 nm minimal step size. A video camera was used to further assist positioning of the tip close to the surface.…”

“…The electric potential of this material changes in response to variations in the acidity of the environment due to its tendency to be coated by a Sb2O3 film. Thus, antimony tips have been employed as pH sensor in SECM for the characterization of a variety of systems [17][18][19], as well as microsensors for other techniques [20][21][22][23][24][25][26][27][28]. Due to the metallic properties of antimony, tips from this material can also be employed in amperometric SECM to image the topography of the substrates under investigation [16,18], thus allowing more information to be gained from these systems.…”

Scanning electrochemical microscopy for the investigation of corrosion processes: Measurement of Zn2+ spatial distribution with ion selective microelectrodes

“…The SECM instrument has been described previously [47]. Main components are a 3D positioning stage driven by stepper motors (MFN 25PP; Newport, Irvine, CA, USA), a battery-powered voltage follower based on an operational amplifier (TL082;…”

Determination of diffusion coefficient in gel and in aqueous solutions using scanning electrochemical microscopy

“…A detailed description has already been published previously [17]. A short summary is only given here.…”