Construction of urchin-like core-shell Fe/Fe₂O₃@UiO-66 hybrid for effective tetracycline reduction and photocatalytic oxidation

Although Fe/Fe₂O₃ has potential application compared with nanoscale zero-valent iron (nZVI), its smooth structure largely limits the catalytic performance. To address this challenge, we innovatively constructed highly efficient composite Fe/Fe₂O₃@UiO-66 via employing an urchin-like core-shell structure of Fe/Fe₂O₃ onto UiO-66 through a facile ion exchange precipitation method without inert gas protection. The characterization results show the urchin-like core-shell configuration can extend the life span of Fe0 and produce more active sites. Besides, the absorption spectrum is broadened by Fe₂O₃ which has narrow band gap and the high-efficiency separation of photogenerated electron-hole pairs is obtained with the load of Fe/Fe₂O₃. Moreover, Two-parameter pseudo-first-order decay model fits well with the reduction and adsorption of composites in the dark reaction, and a plausible pathway for tetracycline (TC) degradation is also proposed. The findings of this research provide a promising method for promoting the catalytic properties of MOF-based materials and Fe/Fe₂O₃.