Ultrafast preparation of hydrophobic ZIF-67/copper mesh via electrodeposition and hydrophobization for oil/water separation and dyes adsorption

Abstract Homogeneous hydrophobic ZIF-67 decorated copper mesh was prepared by ultrafast electrodeposition and subsequent hydrophobization with stearic acid or 1-dodecanethiol. The preparation can be completed within 9 min under room temperature. Based on the hard-soft-acid-base (HSAB) theory, there exists difference of the interaction between Co2+ and specific groups (carboxy or sulfhydryl), the oil/water separation and dyes adsorption performances were thus affected after ZIF-67-coated copper mesh was hydrophobized. The separation efficiency of the hydrophobic meshes for various oil/water mixtures was all greater than 98%, and remained almost no decline after several cycles of separation. However, the intrusion pressure of ZIF-67/copper mesh modified by 1-dodecanethiol is higher than the one modified by stearic acid. At the same time, the 1-dodecanethiol modified ZIF-67/copper mesh displayed a high adsorption capacity for Congo red (near 2000 mg/m2), while the adsorption rate of the mesh modified by stearic acid is significantly faster. This work proposed a simple and fast method to build continuous, homogeneous MOFs film for oil/water separation and dyes adsorption.