Uncovering Photocatalytic Mechanisms toward Water Treatment by Operando Super-Resolution Reaction Imaging
Chuanbin Wang, Jingnan Tian, Qian Tan, Jin Xie, Guanyi Chen, Yan Chen, Xianwen Mao
Abstract
Photocatalytic reactions leveraging nanoscale catalyst particles are vital for sustainable environmental remediation but often involve highly complex mechanisms that are difficult to probe due to the pervasive spatiotemporal heterogeneities in the structure and reactivity of the constituent nanosized photocatalyst particles. Super-resolution reaction imaging, with its high spatial and temporal resolution under realistic operando conditions, enables the real-time observation of photocatalytic reaction kinetics and multifaceted charge carrier behaviors at the nanoscale. However, no comprehensive review has yet explored how state-of-the-art super-resolution reaction imaging techniques inform the photocatalyst design for water treatment. This review aims to bridge that gap by providing an overview of the principles and unique advantages of super-resolution catalysis microscopy and related operando imaging tools. We also highlight how these in situ operando techniques can be applied to investigate structure-property relationships in photocatalysts at the single particle and subparticle levels. Key aspects such as size effects, crystal facet effects, bimetallic effects, heterojunction interface effects, defect effects, and particle aggregation effects will be examined through recent case studies, focusing on their impact on photocatalytic water decontamination efficiency. Finally, we discuss the challenges and future directions of leveraging super-resolution microscopy to distill materials design principles in advancing photocatalytic water treatment.