Iron biochar synergy in aquatic systems through surface functionalities electron transfer and reactive species dynamics

Abstract

The removal of organic pollutants from water by advanced oxidation has been successfully achieved using iron–biochar (Fe–BC)-based material. By embedding iron particles on the biochar, the resulting Fe–BC composite possesses enhanced surface functionalities that promote electron transfer and generate reactive oxygen species (ROS). Characterizations using various analytical techniques confirm the successful formation of the Fe-based biochar and its improved catalytic features. Batch degradation experiments have demonstrated that Fe–BC exhibits significantly higher performance than unmodified biochar in the breakdown of organic contaminants, primarily through advanced oxidation processes (AOPs) facilitated by iron-induced radical (SO₄^•−, ^•OH, O₂^•−) formation, non-radical ROS (¹O₂), and electron transfer pathways. Finally, the advantages of Fe-BC in the catalytic degradation of organic pollutants are summarized, highlighting potential limitations and prompting further research to optimize Fe–BC performance and expand Fe–BC applicability.