Janus hollow fiber membrane with a mussel-inspired coating on the lumen surface for direct contact membrane distillation

• Janus membranes are fabricated by single-sided PDA/PEI deposition on PP hollow fibers.
• Thickness of the hydrophilic layer can be facilely adjusted by the deposition time.
• The Janus membranes exhibit up to 120% improvement in the water flux for DCMD.
• Good operational stability and high salt rejection are obtained with Janus membranes.