Enhanced antifouling performance for modified carbon nanotubes filtration cathode by the electric field

A carbon nanotube filtration cathode as an air-cathode used in microbial fuel cells is fabricated following the phase inversion method, which couples membrane filtration with catalytic reduction. This novel activated carbon/carbon nanotube filtration cathode exhibits the superior electro-conductivity and antifouling performance. The filtration cathode with 10 wt% carbon nanotubes (CNT10) produces a maximum power density of 1469 ± 9.7 mW m⁻², which is 49% higher than that of the unmodified electrode (control). Cathode CNT10 exhibits the lowest charge transfer resistance of 17.9 ± 0.9 Ω which is 64% lower than that of the control electrode. The minimum filtered total chemical oxygen demand of CNT10 is 23.1 ± 1.4 mg L⁻¹, which is 76% lower than that of the control (97.5 ± 3.6 mg L⁻¹). With an additional voltage of 1.5 V, CNT10 exhibits the highest bovine serum protein and humic acid rejection rates, indicating that the applied voltage improves both antifouling performance and electrochemical activity compared to those of the control cathode. These results demonstrate that the conductive filtration cathodes exhibit the better antifouling performance and electrochemical response.