Tip effects in the scanning-tunneling microscopy of semiconductor electrodes

The surface properties of a WSe2 electrode have been investigated with a scanning-tunneling microscope in an electrochemical cell. Current–potential curves have been obtained for various electrode potentials and tunneling distances. They show a strong influence of the tip on the local electrode potential. The main features can be understood within a simple model describing the distribution of the electrostatic potential and its effect on the local electronic density.