Polyoxometalate-Mediated Photoinduced Electron Transfer and Photocatalytic Activity of Donor-Acceptor Hybrid...

Donor-acceptor hybrid materials, recognized as a special class of hybrids, have garnered considerable attention due to their ability to achieve efficient electron-hole separation under light irradiation, accompanied by variations in their chemical and physical properties. To elucidate the effect of the inorganic component on the photochromism and photocatalytic activity of these donor-acceptor hybrids, two isostructural perylenediimide-based materials, PDI-PW and PDI-PMo, featuring different polyoxometalates (POMs), were prepared via self-assembly. Under Xe lamp irradiation, these materials exhibit reversible photochromism that is perceptible to the naked eye. PDI-PMo demonstrates a markedly faster photoresponse rate compared to PDI-PW. Furthermore, both hybrid materials could be easily photoreduced to form their radical anions (PDI^•-), which showed a remarkable POM-dependent photocatalytic activity in the oxidation of sulfides and the oxidative decarboxylation of arylacetic acids. Higher photocatalytic activity was obtained for PDI-PMo, whereas lower conversions were observed for PDI-PW, a behavior mainly attributed to the difference in electron-transfer rate and carrier lifetime. The established structure-property relationships in this work provide a foundation for constructing new light-harvesting systems using electron-deficient dyes and will facilitate the development of materials with novel properties.