Designing polyoxometalate-based metal-organic framework for oxidation of styrene and cycloaddition of CO2 with epoxides
Xiaomei Yan a, Jiangbo Xu a, Ting Zhang a, Chen Si a, Jiachen Jiao a, Jie Li b, Qiuxia Han a,∗

A photoactive polyoxometalate-based metal-organic framework (POMOF), NiW-DPNDI, was synthesized
by combination of Ni(II) ions, [ZnW12O40]6– anions, and N,N’-bis(4-pyridylmethyl)naphthalene diimide
(DPNDI) molecules into one single framework. NiW-DPNDI displays a three-dimensional structure by
the strong anionπ interactions between the trapped [ZnW12O40]6– anions and the electron-deficient
naphthalenic ring centroids and the π-π stacking interactions between DPNDI moieties. NiW-DPNDI
displayed a highly efficient hole-electron separation and ordered electron transfer under irradiation, thus
ensuing its excellent photocatalysis in oxidation of styrene to produce benzaldehyde. In addition, it gave a
high efficiency for styrene oxide under thermocatalytic conditions. Because the carbonic anhydrase (CA)-
mimicking Ni sites and the negative electron-enriched [ZnW12O40]6– anions are well aligned in the pores,
it can promote the cycloaddition of CO2 with epoxides under mild conditions.