Defect‐Engineered Metal‐Organic Frameworks for Photocatalytic Implementations

Defect engineering in metal–organic frameworks (MOFs), particularly the introduction of oxygen vacancies, has emerged as a transformative strategy to enhance their photocatalytic performance. This chapter explores the synthesis protocols for oxygen vacancy-rich MOFs, including post-synthetic modification (e.g., chemical etching, thermal annealing, and plasma treatment) and in situ defect introduction (e.g., solvent/pH modulation and ligand defect design), alongside advanced characterization techniques (XRD, EPR, XAFS, and DFT) to elucidate defect structures and electronic interactions. Oxygen vacancies improve light absorption, charge separation, and surface reactivity, enabling efficient applications in energy conversion (hydrogen production, CO 2 reduction, and water splitting) and environmental remediation (organic pollutant degradation, heavy metal removal, and VOC capture). Despite these advantages, challenges such as precise defect control, stability under operational conditions, and mechanistic ambiguities persist. Future research must address scalability, defect-dynamics analysis, and hybrid system optimization to bridge laboratory innovations with industrial applications.