Decoding mass transport in electrochemical systems via in situ laser interferometry

Abstract

Probing ion transport dynamics at electrode–electrolyte interfaces is essential for advancing electrochemical energy technologies. Among various diagnostic methods, laser interferometry stands out as a label-free, non-invasive optical technique with high spatiotemporal resolution, which is uniquely suited for in situ visualization of interfacial concentration fields. This work outlines the fundamental optical principles and system configurations of laser interferometry, including Mach–Zehnder interferometers and digital holography. Key data processing strategies for concentration field reconstruction are presented, including fringe shift analysis, phase-shifting interferometry, and digital holography. Representative applications are discussed, with a focus on interfacial concentration evolution, metal electrodeposition and dendrite growth, and mass transport under magnetic or convective effects. By bridging optical interferometry with electrochemical interface science, this work provides a comprehensive methodological framework and offers practical guidance for researchers exploring mass transport phenomena and optimizing the performance of electrochemical systems.