In situ Observation of Heterogeneous Charge Distribution at the Electrode Unraveling the Mechanism of Electric Field-Enhanced Electrochemical Activity

Here, in situ observation of heterogeneous charge distribution at the Pt-graphite surface in the hydrogen evolution reaction (HER) is realized using scanning ion conductive microscopy (SICM). High charge density and electrochemical activity are revealed at the Pt-graphite interface, where a high electric field is observed through theoretical derivation. This key information helps to develop a new electrochemical mechanism for the regulation of electrochemical activity, in which a locally high electric field induces more charges in these specific regions and elevated electrochemical activity.