“Nickel and cobalt catalysis in biomass carbonization for bio-anodes in microbial fuel cells: Impact on structure and electrochemical performance”

Abstract

The anode is a very critical element that affects the performance of microbial fuel cells(MFCs). Carbonization of biomass has proven to be a sustainable and efficient technique for making carbonaceous 3D anodes for MFCs. Moreover, transition metals are known for their catalytic potential in the carbonization process and electrochemical devices. In this study, we catalyze the carbonization of cabbage core waste using Nickel and Cobalt through a very simple technique and use them as anodes in double-chamber MFCs. The morphology and structure of the resulting electrodes were compared to those of the same type of biomass carbonized without modification. Additionally, their electrochemical performance was compared by using them in MFCs. The maximum power density values obtained were 904.6, 170.3, 71.2, and 42 mW/m2 for the CW-800, Ni-800, Co-800, and carbon felt, respectively. The decrease in power density in MFCs assembled with the modified anodes can be attributed to the toxicity of the metals to the microorganisms. The findings of this study highlight the importance of balancing the concentration of doped metals in anodes used in MFCs. This work supports the advancement of the UNSDGs by contributing to Goals 6 (wastewater reuse), 7 (renewable bioenergy), 9 (low-cost green technologies), and 12 (circular resource use). The integration of microbiological and materials analysis offers a robust pathway for developing eco-friendly, high-performance MFC anodes.