A stable bimetallic MOF (Ti, Zr)-graphene oxide composite membrane with synergistic anti-fouling strategy of photocatalysis and hydration layer for efficient separation of oily emulsions

作者：Lan Ma, Xinmei Shi, Guilan Zhang, Xin Wen, Chunhun Liu, Xiaoyang Ma, Minghang Jiang, Jianping Li, Liyun Zhang · 发表于：Separation and Purification Technology · 年份：2025 · DOI：10.1016/j.seppur.2025.136016 · 被引用次数：6 · 研究领域：Surface Modification and Superhydrophobicity、Membrane Separation Technologies、Solar-Powered Water Purification Methods

Coupling the principle of super-wetting with photocatalytic technology to obtain strong anti-fouling separation membrane is a promising strategy for sustainable treatment of oily wastewater. Herein, we designed a bimetallic MOF (Ti, Zr) composite by MOF-on-MOF growth strategy, and prepared a strong anti-fouling graphene oxide (GO)/MOF (Ti, Zr) composite membrane (GO/UIO@MIL). The hydrophilic MOF (Ti, Zr) with unique micro/nano-rough architecture endowed exceptional surface superhydrophilicity (WCA < 9.2°) and underwater superoleophobicity (UWOCA >161.2°) for the GO/UIO@MIL-4 membrane, which demonstrated remarkable anti-crude-oil adhesion properties. Meanwhile, The GO/UIO@MIL-4 membrane also achieved both high permeation flux (>2010 ± 55.6 L·m −2 ·h −1 ·bar −1 ) and separation efficiency (>99.4 %) for six surfactant-stabilized oil-in-water emulsions by electrostatic demulsification and capillary interception effect. Notably, the composite membrane displayed excellent chemical and mechanical stability under corrosive environment (pH = 1–13, and salt solution) and physical destruction, which can achieve outstanding separation capability by GO nanosheet bonding the UIO@MIL. Furthermore, the bimetallic MOFs with Zr and Ti metals also increased the pathway for generating active free radicals under light radiation, which endowed the composite membrane surface with photocatalytic degradation performance of organic compounds. Importantly, the synergistic effect of photocatalysis and h...