Upcycling biomass waste into Fe single atom catalysts for pollutant control

Contaminants of heavy metals and antibiotics, which are frequently detected in water, soil and food chains with increasing prevalence in our current society, can cause potential harm to human health and disrupt human ecosystem irreversibly. Herein, we have successfully utilized biomass waste ferns contaminated by iron mines, to fabricate a first-of-its-kind high-performance class of Fe single-atom catalysts (FeSAC) by a facile pyrolysis. The optimal FeSAC-800 shows an excellent efficiency in the fast-photocatalytic degradation of six types of quinolone antibiotics (e.g., norfloxacin, levofloxacin, ciprofloxacin, enrofloxacin, lomefloxacin, flumequine) in 1 h under the simulated natural light irradiation. Based on advanced characterization, a well-defined structure of FeN4, confined in the porous carbon is elaborated for the FeSAC-800. Mechanism of the photodegradation is via a Fenton-like oxidation process whereas the reactive oxygen species play a key role. These findings open a new avenue for efficient, sustainable utilization of biomass waste in pollutant control.