Conjugated microporous polymer-coated sponges for effectively removal of oils and trace aromatic pollutions in water

Efficient elimination of organics or oils in water has become a global concern due to their severely environmental pollution. In this work, two kinds of absorbents based on the doping of conjugated microporous polymers onto sponges (CMPs@sponges) were prepared by in situ Sonogashira-Hagihara coupling reaction of the monomers in the presence of melamine sponge. The as-synthesized CMPs@sponges possess excellent thermal and physicochemical stability. Owing to the excellent hydrophobic character of the CMPs@sponges, which exhibit high oil/water separation efficiency through adsorption process. The CMPs@sponges show desirable ability for the adsorption of oils and organic solvents with the values of 24–64 g/g and 13–36 g/g, and the adsorption properties remain unchanged after 10 cycles with excellent cycling stability. Even the CMPs@sponges are immersed in different pH solutions, which still maintain their original superhydrophobicity. In addition, CMPs@sponges can constantly separate and recover oil and organic solvent based on the help of vacuum pump, and the separation efficiency still remained above 95% after 10 repetitions. It was worth noting that the CMPs@sponges can remove not only the organic solvents but also the trace benzene contaminants from water, and with the removal rate of more than 85%. Furthermore, the as-synthesized CMPs@sponges possess high oil/water separation properties that may be attributed to the physical adsorption, and the π-π interactions and hydrophobic interactions. Therefore, due to the designable flexibility of CMPs, which make the CMPs-based novel materials are excepted to an excellent candidate for applications of oil/water separation and water purification.