Bioinspired hierarchical Zr-MOFs with alkaline-grafted active sites for solid-phase hydrolysis of nerve agent simulants

Zirconium-based metal-organic frameworks (Zr-MOFs) are highly promising for the catalytic degradation of toxic organophosphate nerve agents. However, their practical application in personal protective equipment is limited because they require external volatile alkaline buffers such as N-2-aminoethylmorpholine (NEM) or basic amines to regenerate active sites during hydrolysis. To overcome this limitation, we mimic phosphotriesterase’s active site and residues by performing post-synthetic modification on two-dimensional Zr-BTB nanosheets and MOF-808 nanoparticles. The process involves sequential surface functionalization with hydrophilic ethylenediaminetetraacetic acid (EDTA), chlorination, and grafting of NEM, yielding multifunctional catalysts Zr-BTB-EDTA-NEM and MOF-808-EDTA-NEM. These composites simultaneously provide high active-site accessibility, strong water vapor adsorption, and an intrinsic alkaline buffer environment, enabling self-buffering catalytic hydrolysis under humid conditions. Notably, Zr-BTB-EDTA-NEM achieves 92% conversion of the nerve agent simulant dimethyl 4-nitrophenyl phosphate (DMNP) under a relative humidity (RH) of 99%. This work demonstrates a single-material platform that efficiently degrades organophosphates via solid-phase catalysis under realistic humid conditions, offering new insights for next-generation protective materials.