CoMn2O4 nanoparticles embed in graphene oxide aerogel with three-dimensional network for practical application prospects of oxytetracycline degradation

Abstract

We proposed a new peroxymonosulfate (PMS) activator that the dispersed CoMn2O4 nanoparticles embedded in nitrogen-doped reduced graphene oxide aerogel (CoMn2O4@N-rGA) with interlinked three-dimensional network via hydrothermal method for oxytetracycline (OTC) degradation. CoMn2O4@N-rGA and PMS (CoMn2O4@N-rGA/PMS) exhibited a high degradation rate of 91.3% within 20 min and a rapid catalytic degradation rate of 0.0729 min−1. The radical pathway system had excellent effects on OTC degradation in a wide range of pH from 3.0 to 9.0 and an outstanding catalytic activity on actual pharmaceutical wastewater. It was attributed to dispersed CoMn2O4 nanoparticles embed in nitrogen-doped reduced graphene oxide aerogel with interlinked three-dimensional network by Scanning electron microscope (SEM). The mechanism was hypothesized that PMS was activated to generate sulfate radical (SO4-) and hydroxyl radicals (OH), which could be confirmed via free radical quenching test and electron paramagnetic resonance (EPR) spectra. Finally, a flow-type setup based on the feedback mechanism with excellent effect on high concentration of OTC and actual pharmaceutical wastewater was designed for verifying the practical value of the system.