Highly efficient peroxymonosulfate activation by Fe[sbnd]Co bimetallic modified metal-organic frameworks-derived polyhedron with enriched oxygen vacancy for tetracycline degradation

Abstract

It is important to propose a targeted solution strategy for the rate-limiting step in peroxymonosulfate activation in order to promote its wider application in advanced oxidation processes. In this study, a novel catalyst with FeCo bimetal doping, rich oxygen vacancy and porous polyhedral structure was prepared by using Fe, Co-doped Metal-Organic Framework as the precursor, which strategically enhanced the abundance and stability of active sites and promoted the adsorption of contaminates and PMS molecules. The M-450 (oxygen vacancy-rich)/PMS system demonstrated superior catalytic activity and interference resistance, in which 100 % of TC could be removed within 5 min. The corresponding reaction rate constant is 1.119 min−1, which is much higher than that of M-0 (without oxygen vacancy). Moreover, a series of studies proved that nonradical pathway (singlet oxygen) accompanied free radicals (sulfate radicals and hydroxyl radicals) collectively contributed to the tetracycline degradation. This study provides new ideas for the design and improvement of the functional catalyst for application in sulfate radicals based advanced oxidation processes.