Asymmetric Wettability Janus Mesh via Electrostatic Printing for Selective Oil-Water and Emulsion Separation

Area of Science:

• Materials Science
• Environmental Engineering
• Chemical Engineering

Background:

• Janus meshes with asymmetric wettability are crucial for selective oil-water separation.
• Challenges exist in creating stable Janus meshes with extreme wettability differences.

Purpose of the Study:

• To develop a novel Janus mesh with asymmetric wettability for effective oil-water and emulsion separation.
• To investigate the stability and separation performance of the fabricated Janus mesh.

Main Methods:

• Fabrication of Janus mesh using electrostatic printing with polydimethylsiloxane/zinc oxide (PDMS/ZnO) and zinc oxide-polyacrylonitrile (ZnO-PAN) precursors.
• Characterization of micro-nanostructures on both sides of the mesh (PDMS@ZnO and ZnO@PAN).
• Evaluation of separation efficiency, flux, cycling stability, and performance under harsh conditions (acidic, alkaline, high temperature).

Main Results:

• The Janus mesh achieved high separation efficiency (>96.3%) for various oil-water mixtures and emulsions.
• High flux of up to 2621 ± 30 L m⁻² h⁻¹ was recorded.
• The mesh demonstrated excellent cycling stability (20 cycles) and stability in acidic, alkaline, and high-temperature environments.

Conclusions:

• The developed Janus mesh offers a stable and effective solution for oil-water and emulsion separation.
• The electrostatic printing strategy provides a viable method for constructing advanced Janus interface materials.
• The material shows potential for low-energy, long-lasting applications in intelligent oil-water separation.