In-Situ hydrothermal growth of gallic acid-derived MOF on electrospun nanofibers for simultaneous oil and heavy metal removal

The increasing discharge of complex wastewater, which poses a significant risk to the environment and health, requires the development of an efficient and versatile treatment technology. In this study, we present a more environmentally friendly bifunctional membrane made by in-situ hydrothermal growth of metal-organic frameworks (MOFs) on electrospun nanofibers that can be used for the simultaneous removal of emulsified oils and heavy metal ions. The electrostatically spun fiber substrate consisting of polyacrylonitrile (PAN) and polyimide (PI) provided a high surface scaffold for the uniform deposition of gallic acid biobased MOFs, which ensured highly efficient adsorption and filtration properties as well as the advantage of facilitating secondary recycling. Excellent separation efficiency (>98.4 %) was demonstrated for oil-in-water emulsions and high adsorption capacity (>291 mg·g −1 ) for heavy metal ions. In addition, the membrane exhibited excellent reusability and stability over multiple cycles, highlighting its potential for practical wastewater treatment. This work not only provides scalable strategies in order to design multifunctional filtration materials, but also promotes the understanding of the function of Bio-MOF enhanced nanofibers in the remediation of complex pollutants.