Article révisé par les pairs
Résumé : The management of iodine species, notorious for their environmental persistence and health risks, requires innovative materials capable of efficient capture and conversion. Herein, we report the self-assembly and characterization of a Zr-based metal–organic tetrahedron (1) functionalized with redox-active triazatriangulenium (TATA+) panels. The cage exhibits a high binding affinity for triiodide (I3−) (ca. 106 M−1) in methanol. The strong host–guest complexation significantly facilitates the disproportionation hydrolysis of I2 to generate I3− and HOI. It also enables photocatalytic aerobic oxidation of I− into I3− within its cavity. Mechanistic investigations revealed the key steps involving guest-to-host photoinduced electron transfer (ET) to generate radicals I• and 1• and ET from 1• to dioxygen to generate superoxide. Solid-state adsorption experiments showed the rapid removal of I2 and I3− from water by 1-NTf2 because of the high affinity for polyiodides. Importantly, although solid-state 1-NTf2 has no ability to directly adsorb I− from water, we have for the first time developed a light-driven strategy that enables removal of I− through coupled photooxidation and sequestration. This work highlights the significant potential of integrating photoredox-active moieties within stable metal–organic cages for controlling iodine binding and speciation and opens new avenues to address environmental and energy-related sequestration challenges.

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