3D‐Printed Macroporous Resin Anode in Microbial Fuel Cell‐Based Biosensors for Efficient Biodegradable Organic Carbon Monitoring

Abstract In this study, a novel 3D‐printed glassy carbon gyroid anode is constructed using stereolithography, aiming to improve microbial fuel cell (MFC)‐based biosensor performance through a simple method that optimizes both the macroporous structure and hydrophilicity of the anode. Comparative studies are conducted between MFC‐based biosensors with traditional carbon felt (CF‐MFCs) and those with the 3D‐printed resin anode (RE‐MFCs). In batch mode, RE‐MFCs show a linear dynamic range from 26 to 405 mg L −1 , +126% higher than CF‐MFCs (26–194 mg L −1 ). However, a reduction in sensitivity is observed (0.40 ± 0.08 mA m −2 mg −1 L −1 for RE‐MFCs and 1.02 ± 0.08 mA m −2 mg −1 L −1 ). In continuous flow mode at a flow rate of 0.1 mL min −1 (HRT = 5 h), the RE‐MFCs demonstrated up to 35% higher sensitivity (1.45 mA m −2 mg −1 L −1 ) than the CF‐MFCs (0.94 mA m −2 mg −1 L −1 ) due to increased mass transport and better biofilm activity. Despite using the same inoculum, different microbial electroactive biofilms formed on the CF and RE anodes. Biofilm communities are influenced more by the operation mode than by the anode material choice. This study introduces an innovative anode material that can be tailored to increase dynamic range or sensitivity based on MFC operation mode and calibration strategy.