Scanning Electrochemical Potential Microscopy (SECPM)

Scanning Electrochemical Potential Microscopy (SECPM) us a sharp needle as the afm probe. Detector signal is the electric potential difference between the AFM tip and sample (or between afm tip and a reference electrode) in an ionic or polar liquid, where an electric double-layer exists at the liquid/sample interface. SECPM charts the electric potential profile across the depth of the double-layer (versus Z, the tip-sample distance) at tip XY location. In feedback mode, the output signal adjusts the Z position of the scanner.