Critical insight into sediment microbial fuel cell: Fundamentals, challenges, and perspectives as a barrier to black-odor water formation

The rise in sediment pollution is threatening the sustainability of the overlying waters and calls for in situ sediment remediation techniques. Sediment microbial fuel cell (SMFC) oxidizes organic and inorganic matter buried in sediment to generate bioelectricity and power environmental monitoring devices. However, the large-scale application of SMFC is hampered by mass transfer limitations of electron donors, poor biodegradation of recalcitrant pollutants, and metabolic product accumulation. The aforementioned challenges arise because active contaminant degradation reactions and electron transfer are restricted to microorganisms attached to the anode that contains active biodegraders and electroactive bacteria. This review critically examined the challenges of SMFC, its fundamental operating mechanisms and performance enhancement strategies. A potential method has been proposed to achieve high-performing SMFC by expanding the radius of influence of biodegradation and electron transfer in sediment through enhancing long distant electron transport. This review has documented fundamental information expected to spur SMFC application in alleviating the toxic black-odor water and other contaminants that endanger the environment.