Facile fabrication of superhydrophobic, superoleophilic photocatalytic membrane for efficient oil-water separation and removal of hazardous organic pollutants

• Published in: Journal of cleaner production Vol. 208; pp. 904 - 915
• Main Authors: Baig, Umair, Matin, Asif, Gondal, M.A., Zubair, S.M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 20.01.2019
• Subjects: Cerium oxide; Membrane; Photo-catalytic degradation; Wettability; Membrane; Photo-catalytic degradation; Wettability; Cerium oxide
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2018.10.079

In this work, the fabrication and characterization of a dual-purpose membrane is reported: (i) oil-water separation with high efficiency, and (ii) effective and rapid photocatalytic degradation of hazardous environmental pollutants. Nanoparticles of a rare-earth oxide, cerium (IV) oxide, synthesized by a simple co-precipitation technique, were spray-coated onto stainless steel membranes to obtain a uniform coating with superwetting characteristics. The as-synthesized cerium (IV) oxide nanoparticles and its spray-coated stainless steel membrane were characterized by advanced analytical techniques. X-ray diffraction, selected area electron diffraction, and electron microscopy results of the cerium oxide particles showed a high degree of crystallinity and uniform particle size of ∼50 nm. Elemental surface analysis using X-ray photoelectron spectroscopy showed the characteristic peaks for Ce4+, thereby confirming the presence of cerium oxide nanoparticles. Contact angle measurements showed the coated membranes to be superhydrophobic (∼150°) and superoleophilic (∼0°). When used in a simple laboratory setup, the membranes were able to separate oil and water with a high efficiency (∼99%). Furthermore, the coated membrane showed enhanced photocatalytic activity under UV light irradiation resulting in the rapid degradation of organic persistent pollutants like MB dye in water. To summarize, this work presents an innovative approach in the application of multifunctional membranes for effective water treatment. [Display omitted] •Facile fabrication of superhydrophobic/superoleophilic and photocatalytic membranes.•Applied for oil-water separation and photocatalytic degradation of dyes.•High efficiency of oil-water separation achieved by nanoparticles coated membrane.•Excellent photocatalytic activity of membrane for removal of toxic organic dyes.