Single-Molecule Localization Microscopy in Photocatalysis: From Nanoscale Dynamics to Multidimensional Materials

Advancing efficient photocatalysts is crucial for sustainable energy conversion and environmental remediation; however, progress has been hindered by limited understanding of nanoscale reactivity and charge dynamics. Single-molecule localization microscopy (SMLM) has recently become an effective tool to address this gap, offering nanometer spatial precision and operando compatibility for visualizing catalytic events in real time. This work highlights advances in applying SMLM to semiconductor photocatalysts of diverse dimensionalities, such as 0D nanoparticles, 1D nanotubes, 2D nanoplates and nanosheets, 3D polyhedral, and heterostructured systems. By mapping turnover heterogeneity and quantifying site-specific kinetics, SMLM enables direct correlation of structural features (e.g., facets, edges, wrinkles, and interfaces) with photocatalytic performance. These insights not only uncover fundamental mechanisms of charge separation and reaction pathways but also provide activity-guided strategies for rational catalyst design. Collectively, the integration of SMLM into photocatalysis research offers a powerful route toward engineering advanced materials for efficient solar-driven chemical conversions.