Development of spectroelectrochemical microscopy for the real-time study of electrochemical surface processes

Abstract

We present a multimodal methodology integrating time-resolved inductively coupled plasma mass spectrometry (ICP-MS) with operando reflected microscopy to characterise electrochemical surface processes. Enabled by a custom scanning flow cell, this approach allows simultaneous high-resolution optical inspection under controlled polarisation and continuous electrolyte flow. While ICP-MS and reflected microscopy have each advanced the study of electrocatalysis and corrosion, their direct combination correlates spatially resolved optical changes with quantitative, time-dependent dissolution kinetics. To illustrate its potential, we examined copper electrodes in dilute NaCl solutions with and without 2-mercaptobenzothiazole (2-MBT), a well-established corrosion inhibitor. The joint analysis distinguished mechanistic regimes of cathodic and oxide dissolution, uniform corrosion, passivation, and localised breakdown by linking morphology and optical features with dissolution profiles. Beyond this case, the methodology provides a versatile platform for operando electrochemical interface characterisation, bridging dynamic surface phenomena with kinetic reactivity.