Titania nanowires coated PEI/P25 membranes for photocatalytic and ultrafiltration applications

• Published in: New journal of chemistry Vol. 42; no. 4; pp. 3020 - 3027
• Main Authors: Jiang, Rui, Wen, Wei, Wu, Jin-Ming
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 2018
• Subjects: Antifouling; Antiinfectives and antibacterials; Flux; Hydrophilicity; Illumination; Light; Membranes; Mercury surface; Microorganisms; Nanowires; Photodegradation; Polyetherimides; Porosity; Rhodamine; Roughening; Serum albumin; Titanium oxides; Ultrafiltration; Water treatment
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/C7NJ04628F

Polymeric membranes incorporated with TiO 2 possess advantages in superhydrophilicity, anti-fouling, anti-microbial and pollutant degradation. Herein, we report a new synthetic route to fabricate TiO 2 composited polymeric membranes for photocatalytic and ultrafiltration applications. A flexible hybrid membrane of polyetherimide (PEI) and commercial P25 TiO 2 nanoparticles was firstly synthesized, which was then surface functionalized by quasi-aligned TiO 2 nanowires adhering tightly to the membrane. The synthetic route involves multi-steps of surface roughening, titanate nanowire deposition and finally hot water treatment. The mercury porosimetry measurement shows that the membrane contains mesopores ranging from 2 to 100 nm with a peak maximum at 26 nm, and the porosity is ca. 48.7%. The TiO 2 functionalized PEI/P25 membranes exhibited high and stable efficiency to enable photodegradation of rhodamine B in water under UV light illumination. They also possessed high hydrophilicity, permeability and resistance to fouling with bovine serum albumin (BSA) solution. The ultrafiltration tests show that the surface roughened PEI/P25 membrane exhibited a pure water flux of 2165 L m −2 h −1 , with a BSA retention rate of only 3.2%. After precipitation with TiO 2 nanowires, the BSA retention rate increased to 93.3% while a high water flux of 595 L m −2 h −1 was still attained. Further UV light illumination of the membrane achieved an increased water flux recovery ratio (FRR) of 88%, which suggests an enhanced antifouling performance when compared with the water rinsed one.