Designing Flexible and Porous Polystyrene/Silver Doped Zinc Oxide Nanocomposite Fiber Sorbents for Oil/Water Separation

Abstract

The aim of this work is to fabricate hydrophobic porous nanocomposite with enhanced oil adsorption capacity and multifunctional features including antibacterial and photocatalytic effect. Zinc oxide (ZnO) and silver doped zinc oxide (Ag-ZnO) nanomaterials are fabricated by sol-gel method and added to polystyrene (PS) fibers which are fabricated by solvent induced phase separation process coupled with electrospinning. The structure and morphology of the nanomaterials and polymer nanocomposites are characterized through scanning electron microscopy (SEM), tunneling electron microscopy (TEM), Fourier-transform infrared spectrospy (FTIR), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) studies, and X-ray photoelectron spectroscopy (XPS). These techniques are capable of confirming distribution of the nanomaterials within the nanocomposite, hence highlighting the effect of the polymer/filler interfacial interactions. The significance of this work is the enhancement of the mechanical, thermal, and wettability properties of PS through the successful incorporation of the nanomaterials. These tests were carried out using universal testing machine, thermogravimetric, and optical contact angle respectively. In addition, the maximum absorption capacity of the sorbent reached 68.54 g/g, 61.23 g/g, and 58.41 g/g for mineral oil, engine oil, and olive oil respectively. In addition to displaying excellent anti-fouling resistance and photocatalytic activity, the prepared polymer nanocomposite exhibited good mechanical strength with young's modulus amounting to 2.77 MPa, which is a sought after property in the oil/water separation related industries.