Hierarchical architectures of Ag clusters deposited biomimetic membrane: Synthesis, emulsion separation, catalytic and antibacterial performance

The synthesis of high-performance materials for purifying oily wastewater, especially stable oil-in-water emulsions that aromatic pollutants present in water, is of growing scientific and technological significance. Novel hierarchical architectures of Ag clusters deposited biomimetic membrane have been synthesized by ingeniously selecting the mussel-inspired polydopamine coatings as an intermedium layer followed by a facile wet chemical reduction method. The target micro-scaled Ag clusters which are composed of innumerable nanoparticles, firmly load on the surface of sub-micrometer polydopamine spheres (PDSs) benefiting from the chelating capacity and benign reduction ability of PDSs. The resultant Ag@PDSs deposited membrane with enormous specific surface area exhibits superhydrophilicity and underwater superoleophobicity, making it highly promising for efficient separation of various surfactant-stabilized oil-in-water emulsions and synchronously excellent catalytic reduction of water-soluble aromatic dyes. Moreover, such a construction mode can effectively prevent the aggregation and possible leaching of Ag particles, which greatly contributes to the outstanding cyclic performance and good antibacterial activity. All these features demonstrate that the two-step strategy is a facile approach to design and exploit the deposited Ag@PDSs composites for diverse actual applications in oil/water emulsion separation, catalysis and antibacterial agent.