Hollow-architected Co3O4 for enhancing Oxone activation to eliminate an anesthetic, benzocaine, from water: A structure-property investigation with degradation pathway and eco-toxicity

Background: As the most widely-used oral anesthetic, benzocaine (BZC), is increasingly detected in municipal wastewater and regarded as an emerging contaminant. Thus, it would be highly imperative to develop useful methods to eliminate BZC from water. However, very few studies have been ever reported, and only photo catalysis of BZC was attempted. Therefore, this present study aims to be the first study of developing the sulfate radical-based chemical oxidation technology (SR-COT) for degrading BZC.Methods: For establishing a useful SR-COT, the oxidant, Oxone, is then adopted and a facile nanostructured Co3O4 is then developed for maximizing catalytic activities of Oxone activation by creating a hollow fluffy Co3O4 nanostructure using CoMOF as a template, followed by a carving-architected treatment to afford the hollow fluffy Co3O4 (HFCC).Significant findings: In comparison to the solid (non-hollow) Co3O4 (SCC), HFCC possesses not only the excellent textural properties, but also superior electrochemical properties and highly reactive surfaces, making HFCC exhibit the significantly higher catalytic activity than SCC as well as traditional Co3O4 nanoparticle in activating Oxone to degrade BZC. The density function theory calculation is performed to investigate the degradation pathway, and the corresponding eco-toxicity is also studied to realize the degradation implication of BZC by HFCC-activated Oxone.

Automated summary

This study aims to develop the sulfate radical-based chemical oxidation technology (SR-COT) for degrading benzocaine (BZC). A hollow fluffy Co3O4 nanostructure (HFCC) was successfully developed using Oxone as the oxidant and CoMOF as a template, which exhibited higher catalytic activity and better electrochemical properties compared to traditional Co3O4 nanoparticles.