Efficient activation of persulfate by C@Fe3O4 in visible-light for tetracycline degradation

A C@Fe3O4 material, Fe3O4 coated with carbon, was prepared by a simple one-pot hydrothermal method. The C@Fe3O4 material was investigated with persulfate (PS) and light to degrade tetracycline (TC) as a function of pH, aeration conditions and quenching. Experimental results suggest that TC was effectively degraded in the C@Fe3O4/PS/Vis system. In addition, due to the availability of different main active species in this catalytic system, TC degradation was possible under both strong acid and strong alkali pH conditions. The presence of dissolved oxygen can also generate oxygen-active species, such as superoxide radicals (O-2 center dot(-)) and singlet oxygen (O-1(2)), to decompose TC organic matter in solution. Simply put, C@Fe3O4/PS/Vis catalytic system removed pollutants by the formation of O-2 center dot(-), O-1(2), hydroxyl radicals (center dot OH) and sulfate radicals (SO4 center dot-) species for degrading TC. In addition, the stability of the C@Fe3O4 material was found to be outstanding.