Recent research progress, challenges and future directions of sediment microbial fuel cell: A comprehensive review

Sediment is often considered to be both a source and a sink of pollutants, and it is essentially significant to select an economical and eco-friendly treatment technology for the purification of water sediment. Sediment microbial fuel cell (SMFC) converts chemical energy into electrical energy by degrading pollutants in sediments, which has the dual value of pollution treatment and electrical energy generation. Therefore, SMFC is considered as a novel technology for green water environment treatment, which has received much attention from researchers for its advantages of high energy conversion efficiency and low cost. This review systematically introduced the research progress of SMFC remediation technology from the following aspects: (1) summarization of SMFC reaction principles and primary classification, clarifying the basic configuration and application categories, further supporting its wide range of applications with great potential value, promising a solid foundation for those engaged in SMFC research; (2) visual analysis of the number of annual publications and keyword co-occurrence clustering of SMFC with the help of CiteSpace software, which indicated that the research on SMFC had shown a rapid growth trend in the past two decades and was expected to enrich new research directions and create greater value in the future; (3) systematic elaboration of SMFC research progress, including power production, removal of organic pollutants, nutrients and heavy metals, which was considered to be a very promising bio-electrochemical technology for simultaneous pollutant removal and electrical energy recycling. Finally, the current challenges of SMFC were concluded and its development direction in sediment bioremediation was foreseen. Therefore, the review could provide preliminary data and theoretical support for beginners in this direction and the high-speed development of SMFC applications.