Peroxymonosulfate activation by graphene oxide-supported 3D-MoS/FeCoO sponge for highly efficient organic pollutants degradation.

To address conventional powder catalysts' recovery and aggregation issues that greatly restrain their practical application, a recoverable graphene oxide (GO)-supported 3D-MoS/FeCoO sponge (SFCMG) was developed through a simple impregnation pyrolysis method. SFCMG can efficiently activate peroxymonosulfate (PMS) to produce reactive species for rapid degradation of rhodamine B (RhB), with 95.0% and 100% of RhB being removed within 2 min and 10 min, respectively. The presence of GO enhances the electron transfer performance of the sponge, and the three-dimensional melamine sponge serves as a substrate to provide a highly dispersed carrier for FeCoO and MoS/GO hybrid sheets. SFCMG exhibits a synergistic catalytic effect of Fe and Co, and facilitates the redox cycles of Fe(III)/Fe(II) and Co(III)/Co(II) by MoS co-catalysis, which enhances its catalytic activity. Electron paramagnetic resonance results demonstrate that SO, ·O and O are all involved in SFCMG/PMS system, and O played a prominent role in RhB degradation. The system has good resistance to anions (Cl, SO, and HPO) and humic acid and excellent performance for many typical contaminants degradation. Additionally, it works efficiently over a wide pH range (3-9) and possesses high stability and reusability with the metal leaching far below the safety standards. The present study extends the practical application of metal co-catalysis and offers a promising Fenton-like catalyst for the treatment of organic wastewater.