A multifunctional superhydrophobic melamine sponge decorated with Fe3O4/Ag nanocomposites for high efficient oil-water separation and antibacterial application

Herein, a multifunctional superhydrophobic melamine sponge was fabricated in mild conditions. The modified melamine sponge presented extraordinary performances including magnetic response, chemical stability under corrosive conditions, fire resistance, superhydrophobicity (WCA, 156.3 degrees), high adsorption capacity for a variety of oils and chemical organics (55.9-99.6 g/g), high durability and recyclability for oil adsorption after 20 cycles of squeezing procedure, and antibacterial activity. These extraordinary performances were associated with the combination effect of intrinsic properties of original melamine sponge, hierarchical micro/nano structures and low-surface-energy chemicals, which were originated from the porous and elastic skeleton of melamine sponge, the increased surface roughness by PDA-adhered Fe3O4 and Ag nanoparticles, and hydrophobic hydrocarbon chain in ODA, respectively. The modified melamine sponge can be applied for continuous adsorption and collection of light oil floating on water surface with the help of a peristaltic pump. It can also be utilized to separate heavy oil under water in a filter funnel driven only by gravity. Besides, the modified sponge can effectively inhibit the growth of diverse pathogens in bacteria-contaminated water. According to all the abovementioned advantages, it can be predicted that the as-obtained sponge will play an important and widespread role in the area of oil recovery and water remediation.