Tailored design of 2D MOF derived carbon boosting the low temperature plasma catalysis for water treatment: The role of graphitization and hierarchical porous structure

Abstract

The application of efficient and non-polluting low-temperature plasma technology to address the growing problem of environmental pollution has received increasing attention in recent years. In this study, two-dimensional (2D) Co-ZIF (Co-ZIF-L) derived hollow carbon nanosheets (Co-HCNSs) with high graphitization rate and high porosity were designed. The advantages of structure and composition endow Co-HCNSs-9 with excellent catalytic properties. To verify the effects of graphitization and hollow structure, Co-ZIF-L derived solid carbon nanosheets (SCNSs-9) and Zn-ZIF-L derived hollow carbon nanosheets (Zn-HCNSs-9) were prepared in parallel. In low-temperature plasma applications, the degradation rate of tetracycline (TTCH) was as high as 97% within 30 min, Co-HCNSs-9/dielectric barrier discharge (DBD) system improved the degradation rate of TTCH and the energy efficiency The degradation mechanism of Co-HCNSs-9/DBD was investigated by quenching experiments as a synergistic effect of hydroxyl radicals (OH), singlet oxygen (1O2) and reactive nitrogen species (RNS). In addition, the effects of common anions and natural macromolecular organic compounds in the water column were investigated. Based on 3D fluorescence analysis, liquid chromatography-mass spectrometry and density functional theory calculations, possible degradation pathways of TTCH were proposed. Finally, the safety and environmental friendliness of the system was verified by biological toxicity tests.