Facile preparation of recyclable Fe@metal phenolic networks-Au system for catalytic reduction of 4-nitrophenol

The strategic design for fabricating metal phenolic networks (MPNs) at different dimension brings potential possibilities to obtain MPNs-based system with controlled structure, biologically tunable physicochemical properties and high responsiveness behavior. Considering adequate Fe ions within Fe-based materials, self-supplied metal ions for polyphenol to form coating layer on the surface are served as a novel and facile strategies to obtain metal-based phenolic networks composites. Combing these, herein, a simple, green and fast strategy was performed to fabricate recyclable Fe@Fe 3+ -tannic acid-Au (Fe@MPNs-Au) system with high efficiency to catalyze the reduction of 4-nitrophenol. The obtained experimental results showed that the catalytic rate of Fe@MPNs-Au for 4-nitrophenol could be improved from 0.4398 min −1 to 1.5804 min −1 with the increase of Au loading. Additionally, the increased Fe 3+ -tannic acid MPNs layer thickness could also enhance the catalytic rate of Fe@MPNs-Au from 0.2226 min −1 to 2.085 min −1 . More importantly, the superior magnetic properties contributed by Fe core make it possible to be easily separated and collected by a magnet from the solution after multiple catalytic reduction reaction. Finally, we hope this strategy can provide a novel paradigm for fabricating metal-based phenolic networks system by in situ coordinating reaction between self-supplied Fe sources and phenolic molecules.