Delineating roles of NbV and ZrIV oxoclusters in aqueous phase degradation of phosphonate nerve agent simulants

Abstract

Nb-polyoxometalates (Nb-POMs) and Zr-metal organic frameworks (Zr-MOFs) are two of the most proven metal-oxide based materials for nerve gas degradation, purported for base and acid hydrolysis mechanisms respectively. We compare nerve-agent simulant degradation between several Nb-POMs plus a Zr-oxyhydroxide cluster, as a soluble surrogate for Zr-MOFs. We conclude that lability of the metal-oxo species and re-hydrolysis of metal fluoride or metal phosphonate bonds is as important, if not more important than acid/base catalysis of the metal-cation.