Bisthiourea immobilized UiO-66-NH2 supported Fe2O3 nanoparticles to accelerate dual centers Fenton-like reaction

In this paper, an efficient catalyst UiO-66-BTU/Fe2O3 was synthesized by using bisthiourea modified zirconium-based metal organic framework (Zr-MOF). The UiO-66-BTU/Fe2O3 system features outstanding Fenton-like activity that is 22.84 times and 12.91 times larger than Fe2O3 and conventional UiO-66-NH2/Fe2O3 system. It also exhibits good stability, broad pH range and recycle ability. Through comprehensive mechanistic investigations, we have ascribed the excellent catalytic performance of the UiO-66-BTU/Fe2O3 system to 1O2 and HO as the reactive intermediates, cause Zr centers can make complexation with Fe to form dual centers. Meanwhile, the CS on the bisthiourea can form Fe-S-C bonds with Fe2O3, reducing the redox potential of Fe(III)/Fe(II) and influencing the decomposing of H2O2, which indirectly regulate the interaction between Fe and Zr to accelerate electron transfer during the reaction. This work exhibits the design and understanding of the iron oxides incorporated in modified MOFs with excellent Fenton-like catalytic performance to remove phenoxy acid herbicides.