Proceedings of MATSUS Spring 2025 Conference (MATSUSSpring25)
DOI: https://doi.org/10.29363/nanoge.matsusspring.2025.465
Publication date: 16th December 2024
Conductive carbon materials gather a matchless combination of exceptional properties, highlighting their availability, relatively low-cost, lightness, sufficient stability and enormous versatility to be prepared in different sizes, shapes, conformations, porous textures and surface compositions, making them excellent candidates to be used as electrodes in various electrochemical technologies. Among them, there stand out the technologies applied in the field of water treatment, like those based on pollutants electrosorption, electrooxidation and biodegradation (in the so-called microbial electrochemical technologies (METs)). In addition, these technologies show great interest in addressing the challenges of water-energy nexus. In this context, the design of carbon properties is of paramount importance for the feasibility and optimization of these technologies. On the other hand, the availability, cost and environmental impact of these materials are key factors for their development and full-scale application.
This contribution revises the carbon properties that determine their performance in electrochemical water treatment applications. Particularly, the influence of microstructure, porosity and surface chemistry on the electrochemical properties of carbons (conductivity, stability, electrochemical double layer, electron transfer, etc.) is analyzed. Furthermore, advances in strategies and tools to control and optimize these properties are discussed. Finally, recent findings on carbon properties stimulating microbial extracellular electron transfer for METs are summarized. In this respect, recent studies demonstrate that certain oxygen surface groups can promote anchorage and/or electron transfer with electroactive bacteria; whereas nanoscale (bacteria-inaccessible) porosity remarkably enhances the microbially derived electrical current. Among different carbon materials, electroactive biochar is proposed as a good candidate for large-scale environmental applications of METs.
The authors gratefully acknowledge the TED2021-131028B–I00 project funded by MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future” and “European UnionNextGeneration EU/PRTR”.