Carbon nanotube filter functionalized with MIL-101(Fe) for enhanced flow-through electro-Fenton

Herein, an electrochemical carbon nanotubes (CNT) filter modified with MIL-101(Fe) has been designed for the electro-Fenton applications by serving as a functional flow-through electrode. Under an electric field, the hybrid filter enabled the in situ generation of H₂O₂via the two-electron oxygen reduction reaction, which promoted the production of HO by the accelerated Fe²⁺/Fe³⁺ cycling of MIL-101(Fe). It was observed that 93.2 ± 1.2% tetracycline and 69.0 ± 0.8% total organic carbon (TOC) were removed in 2 h under the optimized conditions. The electron paramagnetic resonance (EPR) analysis and radical scavenging experiments revealed that HO predominated the tetracycline degradation. As compared to the batch reactor, the performance of the proposed system was improved by 5.6 times owing to the convection-enhanced mass transport. The plausible working mechanism and degradation pathway were also subsequently proposed. The findings reported in this study provide a promising insight for the environmental remediation by integrating nanotechnology and Fenton chemistry.