Optimizing microbial fuel cells for wastewater treatment: material advances, design strategies, and application...

Microbial fuel cells (MFCs) represent a revolutionary wastewater treatment technology that can simultaneously achieve pollutant degradation and energy recovery. In recent years, advancements in electrode materials (such as graphene-TiO₂ composites) and reactor design have increased their power density to 17.8 W/m² and the chemical oxygen demand (COD) removal rate to over 89%. This review systematically analyzes these materials and modular designs, aiming to address key challenges such as interface electron transfer and mass transfer limitations. The article assesses the applications of MFCs in emerging fields such as nutrient recovery (e.g., anode-driven denitrification increases the total nitrogen removal rate by 19.8%), high-sensitivity biosensing (e.g., BPA detection sensitivity reaches 0.238 mV/(mg/L)), and decentralized wastewater treatment. In response to cost and stability obstacles in the commercialization process, this paper proposes strategies such as performance standardization and microbial community optimization. The analysis indicates that MFCs possess the dual functions of "energy-producing" wastewater treatment systems and real-time water quality monitoring platforms, providing a clear technical path for transitioning from laboratory to industrial applications. This review offers a critical synthesis that extends beyond mere performance comparisons. It establishes application-oriented evaluation frameworks, proposes value-tiered commercialization strategies, and aims to bridge the critical gap between laboratory-scale achievements and industrial feasibility.