Heavy metal elimination based on metal organic framework highly loaded on flexible nanofibers

Abstract

Efficient adsorbents for removal heavy metals are extensively urgent in modern society. Metal-organic frameworks (MOFs) with abundant porosity and tunable structure make it potential to access the advantages of high permeability and adsorbability in water pollutant control. However, MOFs nanoparticles inconvenient to recycle in solution hinder its application in water pollutant treatment. Herein, we report an in-situ growth and large-scalable manufacturing method to fabricate ZIF-8 nanoparticles on electrospun polyacrylonitrile (PAN) nanofibers membrane (ZIF-8/PAN NF) by hot pressing. Consequently, the prepared ZIF-8/PAN NF possesses high loading, uniform dispersion and large-scalable area as well as good flexibility. The fabricated ZIF-8/PAN NF exhibits excellent performance with fast flux (12,000 L/(m²h)) and high filtration efficiency (96.5%) for Cu²⁺ in dynamic adsorption. Additionally, adsorption and electrochemistry are introduced simultaneously. The Cu²⁺ removal rate of ZIF-8/PAN NF reaches 34.1% in 4 min with combination of adsorption and electrochemistry. While it is 29.2% for Cu²⁺ elimination in adsorption. Given the outstanding performance and easy manufacture, this study might bring MOFs powder to eliminate water pollution into practical application.

Keywords: Cu(2+) adsorption; Electrospinning; Hot-pressing; Metal−organic frameworks; ZIF-8/PAN nanofibers.