S-Scheme Shapes Heterojunction Photocatalysis

system supported by in situ irradiated X-ray photoelectron spectroscopy (ISIXPS)─we have expanded its material scope across multiple dimensional architectures, including perovskite materials, semiconducting quantum dots (QDs), conjugated polymers (CP), metal-organic frameworks (MOFs), and covalent-organic frameworks (COFs). To validate the S-scheme mechanism, elucidate charge transfer dynamics, and resolve reaction mechanisms, we have employed an array of state-of-the-art characterization techniques, such as light-irradiated Kelvin probe force microscopy (KPFM), in situ electron paramagnetic resonance (EPR), in situ X-ray absorption spectroscopy (XAS), and femtosecond-transient absorption spectroscopy (fs-TAS).Our most recent efforts focus on composition tuning, defect modulation, and interfacial bonding engineering to optimize the separation and lifetime of photogenerated carriers. Through these strategies, we aim to reinforce the internal electric field, regulate band bending, and precisely control charge flow pathways, ultimately maximizing photocatalytic efficiency. This Account provides a concise yet comprehensive overview of the evolution of SH, with emphasis on the design principles and advanced characterization techniques developed and adopted by our group. We summarize key strategies for engineering SH tailored for enhanced charge carrier separation and highlight their applications in major photocatalytic reactions. Finally, we outline promising future directions for the field.