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Oil-water separations are helping with urgent issues due to increasing industrial oily wastewater, as well as frequent oil spill accidents. Membrane-based materials with special wettability are desired to separate oils from water. However, fabrication of energy-efficient and stable membranes that are suitable for practical oil-water separation remains challenging. Zeolite films have attracted intense research interest due to their unique pore character, excellent chemical, thermal and mechanical stability, etc. Here we first demonstrate zeolite-coated mesh films for gravity-driven oil-water separation. High separation efficiency of various oils can be achieved based on the excellent superhydrophilicity and underwater superoleophobicity of the zeolite surface. Flux and intrusion pressure are tunable by simply changing the pore size, dependent on the crystallization time of the zeolite crystals, of the zeolite meshes. More importantly, such films are corrosion-resistant in the presence of corrosive media, which gives them promise as candidates in practical applications of oil-water separation.

Materials with selective wettabilities are widely used for effective liquid separation in environmental protection and the chemical industry. Current liquid separation strategies are primarily based on covalent modification to control the membranes’ surface energy, or are based on gating mechanisms to accurately tune the gating threshold of the transport substance. Herein, we demonstrate a simple and universal polarity-based protocol to regulate the wetting behavior of superamphiphilic porous nanofibrous membranes by infusing a high polar component of surface energy liquid into the membranes, forming a relatively stable liquid-infusion-interface to repel the immiscible low polar component of surface energy liquid. Even immiscible liquids with a surface energy difference as small as 2 mJ m−2, or emulsions stabilized by emulsifiers can be effectively separated. Furthermore, the infused liquid can be substituted by another immiscible liquid with a higher polar component of surface energy, affording successive separation of multiphase liquids.

An intelligent pH-responsive carrier and release system based on DNA nanoswitch-controlled organization of gold nanoparticles (AuNPs) attached to mesoporous silica (MS) has been designed and demonstrated.

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