Photochromic Polyoxoniobates with Photoinduced D-f-A Electron Transfer Mechanism

Compounds with redox activities have appealing applications in catalytic, electronic and magnetic properties, but the redox inert of polyoxoniobates (PONbs) significantly limits their applications for a long time. In this work, we are able to integrate organophosphate and lanthanide cluster into PONb to create the first family of inorganic-organic hybrid organophosphate-Ln-PONb composite clusters. These novel species not only present the first family of redox active PONbs that can be reduced to form long-lived heteropoly blues under ambient conditions, but also a new photochromic system. More importantly, the analyses of the electronic configurations and photochromic properties for a series of designed proof-of-concept PONbs models allow us to discover a D-f-A electron transfer mechanism, that is, photoinduced electron is transferred from a photosensitive organophosphate electron donor (D) to the Nb-V electron acceptor (A) through the unoccupied 4 f-orbitals of Ln (f). This work paves the way for developing diverse PONb-based redox materials and expanding the possibility of the applications of PONbs in the redox chemistry.

Automated summary

In this work, organophosphate and lanthanide cluster were successfully integrated into polyoxoniobates (PONbs) to create the first family of inorganic-organic hybrid organophosphate-Ln-PONb composite clusters. These novel species not only exhibit the redox activity of PONbs that can form long-lived heteropoly blues under ambient conditions, but also possess photochromic properties. The discovery of a D-f-A electron transfer mechanism through the analysis of electronic configurations and photochromic properties opens up possibilities for developing diverse PONb-based redox materials and expanding the applications of PONbs in redox chemistry.