Nanometer Scale Scanning Electrochemical Microscopy Instrumentation

We
report the crucial components required to perform scanning electrochemical
microscopy (SECM) with nanometer-scale resolution. The construction
and modification of the software and hardware instrumentation for
nanoscale SECM are explicitly explained including (1) the LabVIEW
code that synchronizes the SECM tip movement with the electrochemical
response, (2) the construction of an isothermal chamber to stabilize
the nanometer scale gap between the tip and substrate, (3) the modification
of a commercial bipotentiostat to avoid electrochemical tip damage
during SECM experiments, and (4) the construction of an SECM stage
to avoid artifacts in SECM images. These findings enabled us to successfully
build a nanoscale SECM, which can be utilized to map the electrocatalytic
activity of individual nanoparticles in a typical ensemble sample
and study the structure/reactivity relationship of single nanostructures.