In-situ growth hierarchical and superhydrophobic flower-like Cu3(PO4)2·2H2O nanosheets based on copper mesh for efficient oil–water separation

Superhydrophobic porous membranes with interconnected open structures for effective treatment oily wastewater have gradually drawn researchers' attentions owing to frequent occurrence of organics leakage accidents. In this paper, we successfully fabricated superhydrophobic flower-like Cu3(PO4)2·2H2O nanosheets on copper mesh surface via in-situ growth strategy and silane coupling agent (A151) hydrophobic modification. Specifically speaking, commercial copper mesh served as substrate and Cu could react with (NH4)2S2O8 and Na2HPO4, forming flower-like micro-nanostructure. As-synthesized materials were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffractometer (XRD). In addition, chemical, mechanical stability and durability of as-prepared materials were also investigated under different condition. The relevant experiment results demonstrated that flower-like Cu3(PO4)2·2H2O nanosheets successfully grew on copper mesh surface, resulting in the formation of rough structure. Modified copper mesh showed superhydrophobic and superoleophilic properties simultaneously with water contact angle (CA) of 151.24° and oil contact angle of 0°, respectively. The as-prepared materials could be used to separate oily wastewater with high separation efficiency (above 95.0%). The mechanism of oil–water separation was investigated in detail based on positive and negative capillary effect. High separation efficiency, excellent stability and durability of superhydrophobic copper mesh make it one of best promising separation candidates for wastewater treatment.