Tetracycline hydrochloride degradation with simultaneous electricity generation by bio-electro-Fenton system configured with carbon-modified Fe, Co dual-metal cathode catalyst

Tetracycline hydrochloride (TCH), which is difficultly degradable and widely used, can induce the generation and dissemination of antibiotic resistance genes (ARGs), seriously threatening the environment and human health. Herein, X% (X = 0, 1, 3, 5) carbon-decorated CoFe2O4 catalysts were developed and were assessed by physical characterization, electrochemical performance and their electricity production capabilities in a bioelectro-Fenton (BEF) system using sodium acetate as the substrate, showing that 5 %C-CoFe2O4 exhibited excellent catalytic performance and electron transfer efficiency. Therefore, the BEF configured with 5 %CCoFe2O4 air-cathode catalyst realized the degradation of TCH and total organic carbon (TOC) across varying concentrations of TCH (0, 10, 20, and 30 mg/L). The BEF system with 30 mg/L TCH has the maximum output voltage (0.575 V), open circuit voltage (0.692 V), power density (0.588 W/m2) and minimum internal resistance (180.293 m Omega/m2) compared to other TCH concentrations. This is attributed to the synergistic effect of microbial fuel cells (MFC) and Fenton reactions promoting continuous oxidation-reduction cycles of Fe3+/Fe2+ and Co3+/ Co2+ at the cathode. Furthermore, it increased the diversity and abundance of microbial communities and inhibited the transmission of ARGs. This work develops a high-performance non-expensive cathode catalyst applied to the BEF system, which can simultaneously remove antibiotics and control ARGs propagation.