Crystals with three-dimensional (3D) stereoscopic structures, characterized by diverse shapes, crystallographic planes, and morphologies, represent a significant advancement in catalysis. Differentiating and quantifying the catalytic activity of specific surface facets and sites at the single-particle level is essential for understanding and predicting catalytic performance. This study employs super-resolution radial fluctuations electrogenerated chemiluminescence microscopy (SRRF-ECLM) to achieve high-resolution mapping of electrocatalytic activity on individual 3D Cu2O crystals, including cubic, octahedral, and truncated octahedral structures. With a spatial resolution below 100 nm, SRRF-ECLM precisely delineates the contours of Cu2O crystals, enabling detailed analysis of activity distribution across distinct facets and interfaces. By quantitatively measuring ECL emission intensities from different planes and joint interfaces, we constructed 3D catalytic activity distributions, offering an intuitive and comprehensive perspective of single-catalyst activity. This approach advances single-particle electrochemical analysis and provides valuable insights for designing more efficient catalysts in energy conversion and chemical synthesis applications.
Keywords: 3D catalysts; crystal facet; cuprous oxide; electrogenerated chemiluminescence; super-resolved imaging.