Sulfonic acid metal-organic frameworks derived iron-doped carbon as novel heterogeneous electro-Fenton catalysts for the degradation of tetracycline: Performance and mechanism investigation

Designing efficient heterogeneous electro-Fenton (HEF) catalysts for in-situ H2O2 generation and organic pollutant degradation in water has become a hot research topic. In this study, a series of novel UiO-66-SO3H/Fe (x)-800 materials were successfully prepared by carbonizing sulfonic acid metal-organic frameworks (UiO-66SO(3)H) doped with iron for tetracycline (TC) HEF degradation. The catalytic performance of UiO-66-SO3H/Fe(x)800 was evaluated by comparing different HEF systems, and the effects of different operating parameters and coexisting substances were investigated. The results indicated that UiO-66-SO3H/Fe(1:1)-800 displayed excellent performance for TC degradation over a broad pH range, with an optimal TC degradation efficiency of 90.10% in 90 min and a low energy consumption of 4.39 kWh/kg/TOC. Furthermore, the superior stability and reusability of this catalyst were proved in continuous cycling experiments with low iron leaching (< 1.000 ug/L). The mechanism exploration demonstrated that TC was mainly oxidized by.OH and O-1(2). In addition, iron-doped porous carbon carrier improved the utilization rate of H2O2 and accelerated the regeneration of Fe2+, which played an important role in the HEF process. The HEF system based on UiO-66-SO3H/Fe(1:1)-800 also exhibited satisfactory performance when treating actual water samples, presenting broad application prospects.

Automated summary

In this study, a series of novel UiO-66-SO3H/Fe(x)-800 materials were successfully prepared and used for tetracycline (TC) degradation in heterogeneous electro-Fenton (HEF) process. The UiO-66-SO3H/Fe(1:1)-800 exhibited excellent TC degradation performance over a wide pH range, with a high degradation efficiency and low energy consumption. The mechanism exploration revealed the important role of iron-doped porous carbon carrier in the HEF process. Moreover, the catalyst demonstrated superior stability, reusability, and satisfactory performance when treating actual water samples.