A dual-functional superhydrophobic PDMS@ZnO@MS sponge for highly efficient oil–water separation and photocatalytic degradation

Abstract

Oily wastewater and soluble contaminants from oil spills, industrial wastewater and domestic sewage have caused serious water pollution. Promisingly, the synergistic treatment technology of adsorption and visible light catalysis is considered to be an effective solution for wastewater purification. In this paper, a dual-functional superhydrophobic polydimethylsiloxane@ZnO@melamine sponge (PDMS@ZnO@MS) was successfully prepared for oil–water separation and photocatalytic degradation of dyes in wastewater. The PDMS@ZnO@MS sponge showed superhydrophobic properties with a water contact angle of 150.5°, and excellent selectivity adsorption for various organic solvents and oils from water. This sponge can effectively separate oil-in-water emulsion. Meanwhile, the sponge has outstanding oil/water separation efficiency (99% after 10 cycles) and oil absorption capacity (2276 wt% after 40 cycles). Notably, the obtained superhydrophobic sponge could withstand chemical corrosion (acid, alkaline, and salt solutions) and demonstrated good thermal stability. Moreover, the PDMS@ZnO@MS sponge was effective for photocatalytic degradation of methylene blue with a degradation efficiency of over 90% under 60 min irradiation. Therefore, the PDMS@ZnO@MS sponge is a promising oil–water separation and photocatalytic material with great potential applications in wastewater remediation.