Designing CuO@rGO-MoS₂ Nanocomposite with Bird’s-Nest Like Structure as Peroxymonosulfate Activator for the Efficient Degradation of Rhodamine B

A straightforward, single-stage hydrothermal approach was utilized to synthesize a unique CuO@rGO-MoS₂ nanocomposite, featuring a nest-mimicking architecture. It has highly efficient heterogeneous catalyzed property that can catalyze and activate the peroxymonosulfate (PMS) by means of radical (•OH, SO₄^•-, and O₂^•-) and nonradical (¹O₂) pathways to generate ROS for the rapid degradation of the organic dye rhodamine B (Rh.B). Graphene oxide, which has high specific surface, serves as an excellent carrier which achieves a homogeneous dispersion of the main catalyst component and gives a series of oxygen-containing functional groups that become active centers for nonradical route activation. Through experimental and DFT calculation, it was revealed that MoS₂ as a cocatalyst accelerated the redox cycle of the Cu active center during the activation of PMS via catalysis, further enhancing the catalytic activity of the nanocomposites. And thus the CuO@rGO-MoS₂/PMS system with bird's-nest like structure achieves rapid degradation of Rh.B in a short period, and the decomposition efficiency of Rh.B reaches 99% within 30 min duration of the reaction. Besides, this system exhibits excellent resistance to environmental interference, demonstrating commendable degradation efficiency across broad pH spectrum (pH 5-11) and high levels of common interfering ions (Cl^-, NO₃^-, SO₄^2-, etc.). To conclude, this study tried to propose and validate a catalyst design idea based on catalytic activation of peroxymonosulfate by selecting appropriate main catalysts, cocatalysts, and catalyst carriers to achieve improved catalytic performance and stability of the catalysts, and the synthesized catalysts CuO@rGO-MoS₂ by this design strategy have shown good degradation performances in real wastewater.