The main aim of the project is to develop novel electrodes, both in material and design aspect for applications in different types of microbial electrochemical reactors such as microbial fuel cell, microbial electrolysis cell and microbial electrosynthesis. In terms of material, the goal is to reduce the content of fluorinated binder in the electrodes (specifically gas diffusion electrodes) and in terms of design, tubular electrode configurations will be explored.

Key methodology will be built upon VITO’s patented and proprietary VITO CORE technology for producing electrodes. Besides carbon-based electrodes which are currently the state of the art for METs, novel metal based, and carbon free electrodes will be developed in this project for improving the performance of MES for CO2 conversion. The experimental approaches will involve material synthesis (developing highly active and selective catalysts for oxygen reduction in MFC and CO2 conversion in MES), electrode development (design of GDE systems that facilitate rapid gas diffusion and reduce mass transport limitations) and optimization of the fabrication parameters such as coating thickness, drying conditions, and binder composition, evaluating the surface-property relationship using characterization techniques such as SEM, AFM, Raman, XRD and BET.

This sub-project with Trampoline is working on the hypothesis of developing non-fluorinated electrodes with similar or better performance than the PTFE based ones currently in use in METs.

The electrodes will be tested by Trampoline partners or the VITO PhD scholar who will test these during the secondments at UAB and UniMiB.

The research is expected to lead to the development of advanced, non-fluorinated gas diffusion electrodes (GDEs) that demonstrate equal or superior performance compared to current PTFE-based electrodes used in microbial electrochemical technologies (METs). These novel electrodes (both metal-based and carbon-based) will enable more sustainable and efficient electrochemical conversion of CO₂, particularly in microbial electrosynthesis (MES) systems and lower cost for MFC and MEC.

The main challenge will be replacing PTFE-based electrodes with non-fluorinated alternatives may affect performance. The risk is that the newly developed electrodes might show lower durability, stability, or catalytic efficiency in microbial fuel cells (MFCs), microbial electrolysis cells (MECs), or MES systems. Another tangible risk is that the novel electrode surfaces or binders could disrupt microbial biofilm formation or electron transfer mechanisms, reducing the system's effectiveness.

UAB (Spain) where the VITO PhD will be registered and carry out a secondment to test the electrodes developed in this project in a MEC; UniMiB (Italy) where the co-supervisor Dr Carlo Santoro is based and will test the electrodes for PFAS remediation in a MET. The developed electrodes in this project will also be tested at University of Girona.