Bioinspired mortise-tenon interlocking HKUST-1/CuOH micro-nano architectures on stainless steel mesh for oil-water separation membranes.

Abstract

The degradation of separation performance caused by the high abrasion of the continuous separation process puts forward more requirements for the adaptability and durability of the oil-water separation membranes. Herein, inspired by the mortise and tenon (MT) structures of ancient Chinese wooden frame buildings, a superhydrophilic and underwater superoleophobic stainless steel mesh (SSM) membrane with HKUST-1-copper hydroxide (CuOH) interlocking micro-nanostructures (HKUST-1/CuOH) was prepared via electrodeposition and hydrothermal growth techniques. The homogeneous growth of HKUST-1 and CuOH with superhydrophilicity and MT structures provides ultral wettability and durability for the HKUST-1/SSM/CuOH membrane. The optimal HKUST-1/SSM/CuOH membrane exhibited a water contact angle of 0° and an underwater oil contact angle of 156°. The flower-like microstructures improve acid and alkali tolerance, organic solvent tolerance, NaCl solution tolerance, thermal resistance, and UV aging performances. In addition, the HKUST-1 and CuOH coatings showed superior and durable antibacterial performance of the HKUST-1/SSM/CuOH membrane. This membrane with an MT structure demonstrated excellent reusability, showing a water flux of 23818 L^.m^-2^.h^-1 and UWOCA of 152.09° after 20 cycles. The proposed method is a promising candidate for unrelenting superhydrophobicity and high permeability in oily water treatment.