Cu-TCPP nanosheets blended polysulfone ultrafiltration membranes with enhanced antifouling and photo-tunable porosity

Abstract

The major obstacle in membrane filtration technology is the membrane fouling, which not only decreases the membrane efficiency, but also enhances its operational cost. In order to fabricate a membrane with antifouling characteristics, potential nanofillers have been added to the engineering polymer(s) to make a composite to improve the membrane efficiency. Herein, we incorporate porphyrin-based ultrathin, highly ordered porous photothermal responsive copper tetrakis(4-carboxyphenyl)porphyrin (Cu-TCPP) nanosheets as a novel nanofillers into the polysulfone (PSf) matrix. High loading (6 wt%) and well dispersed Cu-TCPP nanosheets incorporated polysulfone nanocomposite (Cu-TCPP/PSf) ultrafiltration membranes are prepared via non-solvent induced phase inversion. The Cu-TCPP/PSf composite membranes demonstrate pronounced antifouling and antibiofouling potential along good separation performance. The nanocomposite membranes demonstrate photo-induced pore tuning due to the local heating of photothermal Cu-TCPP nanosheets by visible light, which further improves the membrane separation efficiency. The Cu-TCPP/PSf composite membrane with 6 wt% Cu-TCPP nanosheets enhances the pure water permeance from 23.42 to 260.61 L·m−2·h−1·bar−1, with improved antifouling potential, precise permeance recovery ratio of 99.13% after three cycles, and good separation performance for 100 and 200 nm particles. Considering relatively moderate cost, facile processing, tunable porosity, durable and good mechanical strength along restrained swelling, the Cu-TCPP/PSf membranes are considered as potential candidate as antifouling/antibiofouling ultrafiltration membranes for water purification.