Scanning electrochemical cell microscopy: A natural technique for single entity electrochemistry

Scanning electrochemical cell microscopy (SECCM) is a robust and versatile scanning electrochemical probe microscopy technique that allows direct correlation of structure–activity at the nanoscale. SECCM uses a mobile droplet cell to investigate and visualize electrochemical activity at interfaces with high spatiotemporal resolution, while also providing topographical information. This article highlights diverse contemporary challenges in the field of single entity electrochemistry tackled by the increasing uptake of SECCM globally. Various applications of SECCM in single entity electrochemistry are featured herein, including electrocatalysis, electrodeposition, corrosion science and materials science, with electrode materials spanning particles, polymers, two-dimensional materials and complex polycrystalline substrates. The use of SECCM for patterning structures is also highlighted.