Journal of Energy Bioscience 2024, Vol.15, No.4, 233-242 http://bioscipublisher.com/index.php/jeb 235 Figure 1 Electron transfer mechanism and application of advanced electrode materials in microbial fuel cells (Adapted from Slate et al., 2019) 3.3 Composite materials Composite materials, which combine the properties of different materials, have been developed to enhance the performance of MFC electrodes. These materials often incorporate carbon-based substrates with metal oxides or other conductive materials to improve conductivity, surface area, and biocompatibility. For instance, NiFe2O4-MXene composites on carbon felt have shown superior bioelectrochemical activity and higher power densities compared to conventional carbon felt electrodes (Tahir et al., 2020). Similarly, hierarchical Co8FeS8-FeCo2O4/N-CNTs@CF composites have demonstrated improved microorganism attachment and faster EET rates, leading to higher power densities and better pollutant removal (Wang et al., 2022). 3.4 Limitations of current electrode materials Despite the advancements in electrode materials, several limitations remain. Carbon-based materials, while cost-effective and stable, may not always provide the highest conductivity or surface area required for optimal performance. Metal-based materials, although highly conductive, can be expensive and prone to corrosion. Composite materials, while offering improved performance, can be complex and costly to produce. Additionally, the scalability of these advanced materials for industrial applications remains a challenge. Further research is needed to develop cost-effective, durable, and high-performance electrode materials to make MFCs economically viable for large-scale applications (Li et al., 2018; Slate et al., 2019; Yaqoob et al., 2021a). 4 Advanced Electrode Materials for Enhanced Performance 4.1 Graphene and its derivatives Graphene and its derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), have shown significant promise in enhancing the performance of microbial fuel cells (MFCs). These materials increase the electrochemically active surface area and improve the electron transfer rate, which are crucial for efficient electricity generation. For instance, a study demonstrated that a polydopamine-reduced graphene oxide (PDA-rGO) modified anode achieved a power density of 2 047 mW·m², significantly higher than unmodified carbon cloth anodes (Li et al., 2020). Another research highlighted the use of a graphene-polyaniline (GO-PANI) composite anode, which showed a fourfold increase in performance compared to unmodified anodes (Yaqoob et al., 2020b). These modifications not only enhance power output but also improve the bioremediation efficiency of toxic metals. 4.2 Carbon nanotubes (CNTs) Carbon nanotubes (CNTs) are another advanced material that has been extensively studied for MFC applications. CNTs provide excellent conductivity and a high surface area, which facilitate efficient electron transfer and
RkJQdWJsaXNoZXIy MjQ4ODYzMg==