Improved potentiometric SECM imaging of galvanic corrosion reactions

[Display omitted] •True simultaneous multiprobe operation with ion selective microelectrodes (ISME).•Faster scan rates for high spatial resolution imaging using deconvolution analysis methods.•The arrangement of various ISME in one single assembly facilitates correction for non-ideal selectivity.•Construction, characterization and application of a Cu(II) ISME. The galvanic corrosion of Zn-Cu systems has been monitored in situ using scanning electrochemical microscopy in the potentiometric mode. Here, the initial studies performed using double-barrel microelectrodes for the simultaneous detection of local pH and Zn ion concentration changes in single lines scans, have been extended to the obtention of 2-D maps of Cu2+ and Zn2+ ions. The construction and calibration of a novel Cu2+ ion selective microelectrode is reported. New scanning algorithms and data evaluation tools have been explored for faster acquisition rates than those limited by the time constants associated to potentiometric response.