In situ observation of heterogeneous charge distribution at the electrode unraveling the mechanism of electric field-enhanced electrochemical activity

Abstract

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.