In situ rapid versatile method for the preparation of zirconium metal-organic framework filters

The development of the rapid preparation of highly stable metal-organic framework (MOF)-based devices provides the possibility of meeting the increasing demands of MOF in industrial applications. However, MOFs experience poor processability and stable high-valence-metal(IV)-based MOFs favor forming either thermodynamically stable metal hydroxides or oxides during their growth and nucleation, which hinders their practical applications. Herein, we present a versatile deep eutectic solvent (DES)-assisted hot pressing method to in situ rapidly prepare six distinct zirconium-based MOF nanocrystals on fibers (denoted as Zr-MOFilters) within 20 min. A small amount of DES promotes MOF precursor contact and accelerates Zr-MOF growth. Temperature and pressure facilitate the formation of Zr-MOFs onto desired substrates. In situ¹H nuclear magnetic resonance spectra and time-dependent Fourier-transform infrared spectra were conducted to elucidate the growth of Zr-MOF nanocrystals. As a proof-of-concept, the abilities of Zr-MOFilters for Cr₂O₇²⁻ and micro(nano) plastics removal have been demonstrated. This strategy paves the way for the rapid fabrication of highly stable MOF-based devices and brings MOFs a step closer to practical application.