A durable mesh decorated with polydopamine/graphene oxide for highly efficient oil/water mixture separation

An environmental-friendly stainless steel mesh (SSM) decorated with polydopamine (PDA) and graphene oxide (GO) for oil/water mixture separation was successfully fabricated via a facile dipping coating method. PDA particles were firstly modified on the mesh surface by the self-polymerization of dopamine. Then, GO was firmly anchored onto the surface of PDA particles through the covalent bonds or electrostatic interaction between GO and PDA. Finally, a SSM/PDA/GO multilevel structure was prepared, which shows superior hydrophilicity and excellent anti-fouling properties due to the hydrophilic functional groups and a thicker water layer confined inside SSM/PDA/GO multilevel structure. Therefore, the as-prepared SSM/PDA/GO mesh with a large oil intrusion pressure (>3 kPa) can separate oil/water mixture with ultra-high flux (∼15,000 L m⁻² h⁻¹), preferable separation efficiency (>99.95%) and outstanding recyclability. Furthermore, the SSM/PDA/GO possesses superior stability under harsh environmental conditions, which indicates that the mesh is a promising candidate for practical oil spill cleanup in harsh conditions, especially in high salty marine environment.