Tuning Photoinduced Electron Transfer in POM‐Bodipy Hybrids by Controlling the Environment: Experiment and Theory

Abstract

The optical and electrochemical properties of a series of polyoxometalate (POM) oxoclusters decorated with two bodipy (boron‐dipyrromethene) light‐harvesting units were examined. Evaluated here in this polyanionic donor‐acceptor system is the effect of the solvent and associated counterions on the intramolecular photoinduced electron transfer. The results show that both solvents and counterions have a major impact upon the energy of the charge‐transfer state by modifying the solvation shell around the POMs. This modification leads to a significantly shorter charge separation time in the case of smaller counterion and slower charge recombination in a less polar solvent. These results were rationalized in terms of Marcus theory and show that solvent and counterion both affect the driving force for photoinduced electron transfer and the reorganization energy. This was corroborated with theoretical investigations combining DFT and molecular dynamics simulations.

Supramolecular assemblies of organo-functionalised hybrid polyoxometalates: from functional building blocks to hierarchical nanomaterials

“…Though the application of advanced analytical techniques for the characterisation of POM-based assemblies and nanomaterials will surely continue to improve, it is also worth highlighting that theoretical studies also remain a considerable challenge owing to the time-consuming calculations required for such large systems containing a large number of heavy atoms. 256 As an example, density functional theory simulations are usually limited to systems containing just 4 discrete POM clusters. The combination of DFT with molecular dynamics simulation methods is, however, particularly well-suited for investigating aggregation processes at the molecular level.…”

Latest progress in covalently modified polyoxometalates-based molecular assemblies and advanced materials

“…The results showed that both solvents and counterions exhibited a major impact upon the energy of the charge-transfer state by modifying the solvation shell around the POMs. Moreover, the smaller counterion and slower charge recombination in a less polar solvent can lead to a significantly shorter charge separation time [69] .…”

Guided Synthesis of a Mo/Zn Dual Single‐Atom Nanozyme with Synergistic Effect and Peroxidase‐like Activity

“…[14] POMs are always connected with other materials through covalent or non-covalent interactions to achieve certain functionalities, such as tailoring electrochemical properties, for example. [15] Amongst them, electrostatic interactions provide a vast platform for the combination of the negatively charged POMs with diverse cationic species. [16] Discrete supramolecular frameworks consisting of explicit coordination sites as the constitutional units, possess rigorous structures and precise positive charges.…”