Co-deposition of catechol/polyethyleneimine on porous membranes for efficient decolorization of dye water

Abstract

Mussel-inspired chemistry has been broadly exploited for multifunctional coatings in the surface modification of applied materials. Polyphenols are ubiquitous in plant tissues and far less expensive than polydopamine for mussel-inspired chemistry. Herein, we report a facile and effective method to modify porous membranes via the co-deposition of catechol (CCh) and polyethyleneimine (PEI). The membrane structures and properties were investigated by ATR/FTIR, XPS, FESEM, zeta potential, water contact angle and pure water flux measurements. The results reveal that the membranes deposited with a CCh–PEI mass ratio of 1 : 0.25 show excellent hydrophilicity, ultrahigh water permeation flux and distinguished surface charges. These membranes were used to decolorize anionic dye solutions during filtration with superior removal efficiencies of over 99%. Moreover, they have good reusability over repeated operations with a simple regeneration process.