Metal‐Organic Frameworks for Dual Photo‐Oxidation and Capture of Arsenic from Water

Despite rapid technological progress, heavy metal water pollution, particularly arsenic contamination, remains a significant global challenge. The stabilization of trivalent arsenic as neutral arsenite (AsIII) species hinders its removal by conventional adsorption methods. While adsorption of anionic arsenate (AsV) species is in principle more feasible, there are only a few adsorbents capable of adsorbing both forms of arsenic. In this work we study the potential of two well‐known families of Metal‐Organic Frameworks (MOFs), UiO‐66 and MIL‐125, to simultaneously adsorb and photo‐oxidize arsenic species from water. Our results demonstrate that the formation of AsV ions upon light irradiation promotes the subsequent adsorption of additional AsIII species. Thus, we propose the combined utilization of photocatalysis and adsorption technologies for water remediation purposes.