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The widespread use of antibiotics in pharmaceuticals and aquaculture has led to their high concentration in wastewater, posing threats to ecological stability and human health. In addressing these challenges, in our preliminary work, the embedding of microbial electrodes in a microbial electrochemical system (MES) demonstrated effective degradation of the antibiotic sulfamethoxazole (SMX) in aquatic environments. However, challenges persist, including low electron utilization efficiency and suboptimal antibiotic degradation rates. This study introduces the modification of microbial electrodes with the bimetallic oxide MnCo2O4 to enhance the electrochemical performance of the MES and the degradation efficiency of SMX. Electrochemical analysis revealed a reduction in system internal resistance by 18.99% following electrode modification. The specific capacitance of the microbial electrodes increased from 232.47 to 483.47 F/g. During operation, the MnCo2O4 -modified electrodes exhibited a 12.41% increase in average SMX degradation efficiency compared to unmodified electrodes. Microbial community structure and correlation analysis indicated a significant rise in the richness and diversity of microbes on the modified electrodes. SMX-degrading bacteria such as Acetobacterium and Trichococcus were notably enriched. This research demonstrates the effectiveness of material-modified electrodes in enhancing electron utilization in microbial electrochemistry, while also offering insights into sustainable bioremediation strategies for surface water. [ABSTRACT FROM AUTHOR]

Anaerobic Membrane Bioreactors (AnMBR) offer numerous advantages in wastewater treatment, yet they are prone to membrane fouling after extended operation, impeding their long-term efficiency and stability. In this study, a coupled system was developed using modified conductive membranes as the filtration membrane for the AnMBR and as the anodic conductive membrane in the microbial electrochemical system, with a total volume of approximately 2.57 L. The research focused on understanding the membrane fouling characteristics of the AnMBR when treating wastewater containing sodium ion (Na+) and magnesium ion (Mg2+). When the system was treating wastewater containing Na+, organic pollutants such as proteins and polysaccharides were identified as the primary causes of membrane fouling. Three experimental groups generating different electric currents exhibited extended operational times compared to the open-circuit control group, with extensions of 30, 24, and 15 days, respectively. Conversely, when treating wastewater with Mg2+, organic–inorganic composite fouling, primarily driven by Mg2+ bridging, emerged as the key challenge, with the experimental groups showing operational extensions of 5, 8, and 23 days, respectively, in comparison to the control group. Analysis of proteins and polysaccharides indicated that electric current played a crucial role in reducing organic fouling in the sludge cake layer. When treating wastewater containing Na+, the effectiveness of membrane fouling control was directly proportional to the electric current, while when treating wastewater containing Mg2+, it was directly proportional to the voltage. [ABSTRACT FROM AUTHOR]