[Research progress in applications of iron-based materials in microbial energy conversion]

Microbial energy conversion refers to the process of converting raw materials such as organic matter (sugars, acids, waste biomass, organic wastewater, etc.) or inorganic substrates (carbon dioxide, ammonia, sulfides, etc.) into renewable energy products, such as hydrogen, methane, ethanol, and electrical energy, through microbial metabolic processes. With the rapid development of synthetic biology and enzyme engineering, researchers can perform targeted modifications on microorganisms and their functional enzyme systems, thereby enhancing the conversion efficiency of substrates to energy products. However, in practical applications, microbial energy conversion still generally faces common bottlenecks such as limited electron transfer, complex metabolic regulation, and low energy conversion efficiency, which severely restrict the energy efficiency improvement and engineering promotion of the system. Iron-based materials, with excellent electron transfer ability, potential as enzyme cofactors, and good magnetic separation performance, are widely used in microbial energy conversion to synergistically improve the energy conversion efficiency and operational stability of the system. This paper systematically reviews the research progress in the applications of iron-based materials in representative microbial energy conversion technologies (such as hydrogen production, methane production, electricity production, ethanol production, and lipid production) and analyzes the key mechanisms by which different types of iron-based materials promote microbial energy conversion. This paper aims to provide theoretical support and technical reference for the construction, optimization, and practical application of efficient iron-based material-microbial coupling systems.