Self-Healing and Superwettable Nanofibrous Membranes with Excellent Stability toward Multifunctional Applications in Water Purification

Abstract

Considering the complexity of toxic ingredients in practical polluted water, the development of energy- and labor-saving and environmentally friendly multifunctional materials to decontaminate wastewater is of great necessity. Herein, a multifunctional branched poly(ethylenimine) (bPEI) and poly(acrylic acid) (PAA)/tungsten oxide/polyacrylonitrile (PP/WO₃/PAN) composite membrane was fabricated by the combination of blow spinning and layer-by-layer methods. The incorporated WO₃ in generated in hydrophilic PAN fibers by spinning the precursor method, which simultaneously reveals remarkable photodegradation performance towards mimetic organic pollutions and excellent antibacterial activity due to their electron synergetic effect. In addition, the micro/nanoporous structure of the PP/WO₃/PAN composite membrane also ensures its good oil-water separation performance. Moreover, the reduction reaction of W atoms in the WO₃ network upon solar irradiation endows the membrane with superior heavy metal ion removal capability. Significantly, the membrane exhibits water-enabled self-healing performance due to the coated polyelectrolyte layer. More importantly, the membrane could be easily scaled-up; was free-standing, durable, and biocompatible; and exhibited no additional toxic effect on the surrounding environments. These outstanding properties make the membrane to have significant potential applications in wastewater treatment.