A routine schematic in every general chemistry textbook shows individual electrons and metal ions undergoing reactions, diffusion, and dissolution at a pair of spatially-distinct electrodes — the cathode and anode — at a metal/solution interface. Yet, the correlation between the anode and cathode over both space and time has never been directly measured at the molecular scale. Physicists, electrochemists, and engineers give vastly different answers spanning orders of magnitude on the distance cathodic electrons can be detected away from anodic sites.  We use single molecule microscopy to determine the spatial and timescales of anode and cathode formation and development are during the corrosion of metal films. We have recently demonstrated that redox-sensing molecules that have become fluorescent either by receiving an electron at the cathode or a metal ion at the anode can be detected at the single molecule scale and can quantify corrosion rates. We are now pursuing super-resolution analysis of the dyes to determine the locations of both the cathode and anode at ~10’s nm spatial and ~1’s ms temporal resolutions. Aspects of optical and sample design to achieve super-resolutions will be discussed, along with our spatiotemporal findings for iron, and future prospects for expanding our technique to metal alloys.

Super-resolution imaging of electron and ion charge transfer during corrosion

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.