Degradation of trichloroethylene by activated persulfate using a reduced graphene oxide supported magnetite nanoparticle

A reduced graphene oxide (rGO) supported magnetite nanoparticle (nFe 3 O 4 ) composite (nFe 3 O 4 /rGO) was synthesized and shown for the first time to be an efficient persulfate activator to generate SO 4 − for trichloroethylene (TCE) degradation. The degradation efficiency of TCE (0.15   mmol   L −1 ) was 98.6% within 5   min in the presence of 6.94   g   L −1 nFe 3 O 4 /rGO with an optimum mass ratio of 1:4 and persulfate concentration of 3.0   mmol   L −1 . By dispersing nFe 3 O 4 on the rGO surface, nanoparticle agglomeration was prevented and the aggregation of the rGO sheets was disrupted. Both the redox effect coupled in nFe 3 O 4 and the electron transfer by functional groups containing oxygen on the surface of rGO enhanced the SO 4 − generation. Given the identified free radical species and the characterization of the nFe 3 O 4 /rGO, a persulfate activation mechanism by nFe 3 O 4 /rGO for the degradation of TCE was interpreted.