Polyoxometalate-Surfactant Assemblies: Responsiveness to Orthogonal Stimuli

Angew Chem Int Ed Engl. 2022 Jun 20;61(25):e202203741. doi: 10.1002/anie.202203741. Epub 2022 Apr 21.

Abstract

Integrating different types of supramolecular interactions opens the possibility to generate nanoparticle surfactants (NPSs) at the liquid-liquid interface that are responsive to multiple stimuli. Here we develop a covalently modified polyoxometalate/β-cyclodextrin (POM/β-CD) organic-inorganic hybrid, consisting of a negatively charged POM cluster with β-CD host groups. The POM/β-CD hybrid can be dispersed in water and interacts at a water/oil interface with ligands dissolved in an oil phase through electrostatic or host-guest interactions, thereby generating POM-surfactants (POMSs) having pH, redox, and guest-competitive responsiveness, respectively. By taking advantage of the jamming of POMSs at the interface, a reconfigurable all-liquid system could be produced that is responsive to orthogonal changes in the external environment.

Keywords: Interfacial Assembly; Jamming Transition; Polyoxometalates; Stimuli Responsiveness.