Nanofiltration

Adhesion

Composite number

Engineering

Ecology

Biology

Biofouling

Materials science

Chromatography

Layer by layer

Layer (electronics)

Tannic acid

Fouling

Biochemistry

Mussel

Chemical engineering

Substrate (aquarium)

Geology

Oceanography

Nanotechnology

Organic chemistry

Membrane

Catechol

Permeance

Composite material

Chemistry

Microfiltration

Permeation

Journal of Colloid and Interface Science

Inspired by the mussel adhesion mechanism, plant polyphenol tannic acid (TA) with abundant catechol groups and hydrophilic Jeffamine (JA) containing amino groups were used in a layer-by-layer (LBL) process to fabricate composite nanofiltration (NF) membranes in this study. Alternately immersing a polyacrylonitrile substrate into individual TA and JA buffer solutions could readily construct a NF membrane selective layer without any pre-treatment to the substrate. The optimised membrane showed a high pure water permeance of 37 L m-2 h-1 bar-1 whilst maintaining rejections higher than 90% towards various dyes with molecular weights ranging from 269 to 1017 g mol-1. Particularly, the obtained membrane exhibited excellent anti-fouling and long-term performance attributed to the hydrophilic membrane surface and covalent bonds in the selective layer. The novel strategy inherited the advantages of a mussel-inspired dopamine material but overcame its disadvantages. The results disclosed in this study not only provide a novel strategy to prepare composite NF membranes, but also facilitate the mussel-inspired LBL design of advanced materials for environmental applications.

Fabrication of high-performance composite nanofiltration membranes for dye wastewater treatment: mussel-inspired layer-by-layer self-assembly