Facile synthesis of graphene-cobalt hydroxide nanocomposite and application in degradation of acid orange 7

Abstract

In this study, a cobalt hydroxide-reduced graphene oxide (Co(OH)2/rGO) composite was synthesized by one-step self-assembly, and used as a catalyst in dye degradation. The catalyst was characterized using X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), energy-dispersive X- ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The catalyst had well-distributed Co(OH)2 nanoparticles on the reduced graphene oxide surface. The catalytic performance of this hybrid material was investigated for the activation of peroxymonosulfate (PMS), and used to degrade acid orange 7 (AO7) dye in aqueous solution. The experimental results showed that the composite had high catalytic activity in the degradation of AO7, and 100% decomposition was achieved in less than 12 min. Total organic carbon (TOC) experiments indicated a high degree of mineralization, suggesting excellent catalytic activity. Stability tests showed that the catalyst was stable in the degradation of AO7 over several runs. AO7 was completely degraded in 16 min in the third run.