Metal-polyphenol coordination networks: Towards engineering of antifouling hybrid membranes via in situ assembly

Metal-polyphenol coordination networks have been actively explored as a facile, rapid and green platform for developing materials. In this study, novel antifouling hybrid membranes are successfully prepared via in situ assembling metal-polyphenol coordination networks and are proposed for oil/water separation application. Based on the coordination-driven cross-linking and assembling of Ti-IV and TA within polyvinylidene fluoride (PVDF) membrane matrix, TA-Ti coordination networks are successfully introduced and uniformly distributed in the as-prepared PVDF/TA-Ti membranes. The effects of the embedded TA-Ti coordination networks on both surface morphologies and pore structures of PVDF/TA-Ti membranes are investigated. The surface chemical compositions of PVDF/TA-Ti membranes are analyzed by energy-dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FTIR). The water contact angle analysis and DSC study on bound water content reveal the outstanding hydration capability of PVDF/TA-Ti membranes, indicating the higher underwater super-oleophobicity and antifouling property of PVDF/TA-Ti membranes. The as-prepared PVDF/TA-Ti membranes exhibit remarkably improved antifouling performance with the flux recover ability increased to a maximum level about 100% for the filtration of oil-in-water emulsions. Overall, this study highlights the promising antifouling potential of TA-Ti coordination networks in designing antifouling membranes, and proposes a facile in situ hybridization method for preparing antifouling membranes derived from versatile metal-polyphenol coordination networks.