Actinide-bearing metal−organic frameworks (MOFs) encompass intriguing structures and properties, but the radioactivity of actinide cripples their applications. Herein, we have constructed a new thorium-based MOF (Th-BDAT) as a bifunctional platform for the adsorption and detection of radioiodine, a more radioactive fission product that can readily spread through the atmosphere in its molecular form or via solution as anionic species. The iodine capture within the framework of Th-BDAT from both the vapor phase and the cyclohexane solution has been verified, showing that Th-BDAT features maximum I 2 adsorption capacities (Q max ) of 959 and 1046 mg/g, respectively. Notably, the Q max of Th-BDAT toward I 2 from cyclohexane solution ranks among the highest value for Th-MOFs reported to date. Furthermore, incorporating highly extended and π-electronrich BDAT 4− ligands renders Th-BDAT as a luminescent chemosensor whose emission can be selectively quenched by iodate with a detection limit of 1.367 μM. Our findings thus foreshadow promising directions that might unlock the full potential of actinide-based MOFs from the point of view of practical application.

Developing ultraviolet (UV) radiation sensors featuring high sensitivity, ease of operation, and rapid readout is highly desired in diverse fields. However, the strategies to enhance sensitivity of UV detection remain limited particularly for photochromic materials, which show colorimetric response toward UV irradiation. Guided by our initial goal of facilitating easier handling, we formulated a viologen derivative ([H 2 L]-SC) incorporating hydrogel-based UV sensor which not only inherits the photochromism of [H 2 L]-SC but also engenders an unprecedented reversible photoelectrochromic response that is absent in either [H 2 L]-SC or hydrogel alone. Judicious synergy between photochromic [H 2 L]-SC and polyacrylamide (PAM) converts the colorimetric response of [H 2 L]-SC into the electrical resistance change of [H 2 L]-SC@PAM, which amplifies the UV sensitivity of [H 2 L]-SC by 2 orders of magnitude. Explicitly, the limit of detection (LOD) for UV decreases from 296.3 mJ/cm 2 based on the UV−vis absorption spectra of [H 2 L]-SC to 2.83 mJ/cm 2 derived from the resistance variation of [H 2 L]-SC@PAM. Moreover, linear correlation between the resistance reduction rate of [H 2 L]-SC@PAM and UV dose rate can be established, rendering it as a dual platform for quantifying both the accumulated UV dose and the instant dose rate. In addition, the proposed strategy based on constructing photoelectrochromic hybrids offers a new pathway to boost the UV sensitivity that could be universal for other photochromic materials.