The green synthesis and sustainable environmental applications of single atom catalysts (SACs) has attracted significant attention and emerged as a forefront of research. Herein, self-dispersion Fe single-atom anchored biochar (Fe-SA-BC) was facilely synthesized by endogenous strategy using hyperaccumulator residues (Sedum alfredii) with intrinsic Zn and Fe. Evaporation of hyper-enriched Zn during high temperature pyrolysis facilitated the formation of defect trapping sites and promoted the atomically-dispersion of intrinsic Fe. Fe-SA-BC exhibited an impressive mass activity of 3.13 x 10(4) min(-1) mol(-1) and excellent PMS utilization, and performed stable Bisphenol A (BPA) removal efficiency with high catalytic ability over a wide pH range and in the presence of groundwater interferences, including inorganic anions and natural organic matter. Fe-SA-BC/peroxymonosulfate (PMS) system enabled the potential difference-driven selective oxidation of electron-rich phenolic pollutants with relatively low ionization potential (IP) via nonradical process (E-IP, < 7.0 eV), which is confirmed by the high correlation (R-2 = 0.977) between Ink(obs) and IP. Theoretical calculation revealed that Fe-N3O1 site in Fe-SA-BC optimized the electronic properties and narrowed the energy gap, facilitating the selective electron transfer from pollutants to the Fe-SA-BC/PMS* complex. Effective remediation of polluted groundwater by vertical continuous-flow Fe-SA-BC/sand column further validated its practical application potential. This study opens a new avenue for upcycling of biomass wastes and green synthesis strategies of SACs, and provides inspiration for further research on sustainable environmental remediation.
