Advanced electrochemical techniques for characterizing electrocatalysis at the single-particle level

Abstract Electrocatalytic technologies play a vital role in the advancement of hydrogen energy and other renewable green energy sources, with nanocatalysts gaining significant attention due to their size-dependent electrocatalytic activity and broad applications. Single-particle electrochemistry offers a powerful approach to investigate the intrinsic catalytic activity and electrocatalytic mechanisms of individual nanoscale systems, thereby enabling a deeper understanding of the structure-activity relationship at the nanoscale. In this review, several cutting-edge high-resolution techniques for examining local reactivity at the single-particle level are discussed, such as scanning electrochemical microscopy (SECM), scanning electrochemical cell microscopy (SECCM), single-particle collision technique, and single-atom/molecule electrochemistry. We begin by concisely elucidating the working principles of these advanced electrochemical methodologies. Subsequently, we present recent advancements in high-resolution electrochemical techniques for characterizing electrocatalysis in detail with valuable insights into the local activity of various catalysts. In future research, the integration of multiple technologies through collaborative analysis is anticipated to further unveil the catalytic active sites of electrocatalysts with intricate structures and facilitate quantitative investigations of complex reaction processes.