Recent Advances in Single-Chamber Photosynthetic Microbial Fuel Cells for Sustainable Bioelectricity Generation: Mechanisms, Performance, and Challenges.

In the face of rising energy demands, environmental degradation, and growing water scarcity, Microbial Fuel Cells (MFCs) offer a promising solution by harnessing waste to generate bioelectricity and treat wastewater. Among these, photosynthetic MFCs, particularly single-chamber systems, offer distinct advantages due to their compact design, sustainability, and dual functionality for power generation and pollution mitigation. These devices convert chemical energy from organic substrates directly into electrical energy via bacterial processes, while also enabling pollutant breakdown and carbon dioxide sequestration. Recently, there has been increased interest in integrating photosynthetic organisms, such as microalgae, into MFCs. Microalgae-assisted MFCs (MA-MFCs) can enhance power production by leveraging sunlight during photosynthesis, which simultaneously produces oxygen, acts as an electron acceptor, and facilitates pollutant degradation. Furthermore, microalgal biomass can serve as an anode substrate for bioelectricity generation. MA-MFCs are notable for their potential to improve Coulombic efficiency and eliminate the need for external aeration. Despite these advancements, challenges persist, including low energy yields and the complexity of upscaling. However, innovative approaches, such as modular MFC stacking, optimized photobioreactor integration, and the usage cost-effective materials, are showing considerable promise. This review examines recent developments, scalability barriers, and future directions in single-chamber photosynthetic microbial fuel cells, emphasizing their applicability in wastewater treatment, sustainable bioelectricity production, and pollutant remediation.