In Situ Growth of ZIF-67 on Cellulose Paper via Mussel-Inspired Chemistry to Construct Superhydrophobic Sheets for Efficient Oil–Water Separation

The development of sustainable and efficient oil–water separation materials remains a challenge, particularly those combining robust stability with additional functionalities. In this work, a mussel-inspired strategy is reported for fabricating a multifunctional superhydrophobic paper via a facile dip-coating process. Cellulose fibers are first modified with a codeposited layer of polydopamine and the aminosilane KH550, which serves as a robust adhesive bridge, enhancing interfacial adhesion and mechanical properties─evidenced by a 51 and 32% increase in bursting and tensile strength, respectively. ZIF-67 nanoparticles are then grown in situ to construct a hierarchical micro/nanoscale roughness, followed by hydrophobic modification with hexadecyltrimethoxysilane. The resulting material exhibits exceptional superhydrophobicity, with a water contact angle of 156°, and demonstrates outstanding self-cleaning, antifouling, and chemical resistance properties. When employed for oil–water separation, it achieves high efficiency (>97%) for various oil–water mixtures and excellent recyclability, maintaining 96% efficiency over 50 cycles. Moreover, the incorporated ZIF-67 confers significant antibacterial activity, with inhibition rates of 70.22% against E. coli and 84.26% against S. aureus. This work presents a scalable and sustainable approach to designing high-performance, multifunctional cellulose-based materials for environmental remediation.