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A silver-modified polyniobotungstate based on Nb/W mixed-addendum polyoxometalate with the formula of Ag9[P2W15Nb3O62]•21H2O (Ag-Nb/W) has been synthesized and characterized by various analytical and spectral techniques. Ag-Nb/W was proved to be an efficient photocatalyst for the oxidative ring openings of 2-phenylimidazo[1,2-a]pyridine via simultaneous cleavage of C-C and C-N bonds. Under visible light (430-440 nm), using oxygen as an oxidant at room temperature, Ag-Nb/W can catalyze the rapid transformation of various 2-phenylimidazo[1,2a]pyridine derivatives to produce the corresponding oxidative ringopening product N-(pyridin-2-yl) amides in good isolated yields ranging from 65% to 78%. As a heterogeneous photocatalyst, Ag-Nb/W showed excellent sustainability and recyclability in the recycling experiments. IR spectroscopy and XRD analysis indicated that Ag-Nb/W could retain its integrity after catalysis. A possible mechanism involving singlet oxygen was proposed for the catalytic reaction.

Chemodynamic therapy (CDT) uses the conversion of H2O2 to ·OH triggered by Fenton‐like reactions to treat tumors, but the treatment is not complete due to insufficient intracellular H2O2 content. Photothermal therapy (PTT) uses photothermal materials for photothermal conversion to kill tumors, but it is limited by the extent of exogenous light transmission and cannot achieve satisfactory therapeutic effects. Therefore, designing a composite nanomaterial that amplifies CDT and couples it with PTT for tumor treatment is a major challenge. Herein, we designed a W‐POM NCs@HKUST‐1 nanoplatform that combines PTT and CDT and has better targeting properties. It shows high stability and photothermal conversion efficiency under the irradiation of near‐infrared light and efficiently catalyzes the generation of intracellular hydroxyl radicals, this composite material exhibits higher lethality than single therapeutic strategies. This study expands the application area of POM@MOF composite nanomaterials and provides a promising means of enhanced tumor therapy.

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