In recent years, bioelectrochemical technology has attracted attention as a potential solution for sustainable energy production. This technology utilizes microorganisms to convert organic matter into electricity, known as microbial fuel cells (MFCs). One of the critical components in MFCs is the cathode, which plays a crucial role in the electrochemical process. This article will discuss the impact of using submerged and floating cathodes on the performance and sustainability of bioelectrochemical systems based on recent research.
Understanding Bioelectrochemical Systems and the Role of Cathodes
Bioelectrochemical systems like MFCs work by harnessing the activity of microorganisms that degrade organic matter in the anode to produce electrons. These electrons then flow through an external circuit to the cathode, where they participate in the oxygen reduction reaction, generating an electric current. The efficiency and performance of MFCs are greatly influenced by the design and material of the cathode used.
Cathodes can be divided into two types based on their position in the system: submerged cathodes and floating cathodes. A submerged cathode is fully immersed in the electrolyte solution, while a floating cathode is partially in the liquid, with the other part exposed to air. Both configurations have advantages and disadvantages that affect the overall performance of the MFC.
Submerged Cathodes: Advantages in Reduction Reactions
Submerged cathodes have full contact with the electrolyte, allowing the oxygen reduction reaction to occur more efficiently. This condition tends to increase electron transfer and reduce resistance in the system, ultimately enhancing electricity production. Moreover, since the entire cathode is submerged, microorganisms can more easily interact with the cathode surface, potentially increasing the rate of bioelectrochemical reactions.
However, submerged cathodes also have some drawbacks. One of these is the potential for excessive biofilm formation on the cathode surface, which can hinder electron transfer and degrade system performance over time. Additionally, maintaining anaerobic conditions around the cathode can be challenging, especially on a larger scale.
Floating Cathodes: A Solution for Enhanced Sustainability
Floating cathodes offer an attractive alternative to overcome some of the issues faced by submerged cathodes. With part of the cathode exposed to air, oxygen from the atmosphere can directly interact with the cathode surface, which can enhance the rate of the oxygen reduction reaction without the need for additional oxygen supply. This not only can increase system efficiency but also reduce the energy required for aeration, making the system more sustainable.
Furthermore, since they are not fully submerged, floating cathodes tend to experience less biofilm formation, which can extend the cathode’s lifespan and reduce maintenance needs. However, the challenge in using floating cathodes is ensuring sufficient contact between the cathode surface and microorganisms in the electrolyte, which is crucial to maintaining system efficiency.
Conclusion: Choosing the Right Cathode for Sustainability
The choice between submerged and floating cathodes largely depends on the specific goals and conditions of the bioelectrochemical system in use. Submerged cathodes may be more suitable for systems requiring high electron transfer and capable of managing biofilm formation. On the other hand, floating cathodes offer a more sustainable solution by reducing energy needs for aeration and minimizing biofilm formation.
Recent research suggests that combining both types of cathodes could also be an effective solution, leveraging the strengths of each to enhance the performance and sustainability of MFCs. As bioelectrochemical technology continues to evolve, it is expected that innovations in cathode design will further support more efficient and environmentally friendly energy production in the future.
Link Journal : https://scholar.unair.ac.id/en/publications/effect-of-submerged-and-floating-cathodes-on-sustainable-bioelect