A novel 3D Co/Mo co-catalyzed graphene sponge-mediated peroxymonosulfate activation for the highly efficient pollutants degradation

Abstract

A novel 3D Co/Mo co-catalyzed graphene sponges (SCMG) was fabricated by a simple impregnation pyrolysis method, and successfully applied as a highly efficient heterogeneous catalyst in peroxymonosulfate (PMS) activation for rapid and complete elimination of rhodamine B (RhB) within 2 min. The introduction of O contributed to enhanced electron transfer ability of the sponge, and 3D melamine sponges as substrates provided a highly dispersed support for Co/Mo heterojunction. MoS2 co-catalysis accelerated Co(III)/Co(II) conversion and promoted the generation of 1O2, which ensured an improved catalytic activity. The main reactive oxygen species in the SCMG/PMS system were 1O2 and SO4.-, which contributed to a high reactivity over a wide range of pH (3–9). SCMG/PMS system were highly resistant to anions (Cl-, SO42- and H2PO4-) and natural organic matter (humic acid), and could be widely used for the degradation of common organic contaminants. Besides, SCMG has good reusability and stability, and the metal leaching was well below existing safety standards over a wide pH range. This work broadens the application range of metal co-catalysis and provides a promising heterogeneous Fenton-like catalyst in refractory organic wastewater treatment.