Sulfur-iron functionalized biochar (BC-Fe-S) was designed by simultaneously supporting Fe₂O₃ nanoparticles and grafting sulfur-containing functional groups onto biochar to stabilize Pb and Cd in soil. The BC-Fe-S exhibited excellent stabilization performance for Pb and Cd with fast kinetic equilibrium within 5 days associating with pseudo-second-order model. The bioavailable-Pb and -Cd contents decreased by 59.22% and 70.28% with 3% BC-Fe-S treatment after 20 days of remediation. Speciation transformation analysis revealed that the increase of stabilization time and BC-Fe-S dosage with appropriate soil moisture and pH promoted toxicities decrease of Pb and Cd with transformation of labile fractions to more steady fractions. The labile fractions of Pb and Cd decreased by 12.22% and 16.21% with 3% BC-Fe-S treatment, and transformed to the residual speciation. Meanwhile, wetting-drying and freezing-thawing aging did not markedly alter the bioavailability of Pb and Cd, proving that the BC-Fe-S holds promise for stabilization of Pb and Cd in varying environmental conditions. 16 S rRNA sequencing analysis demonstrated that the BC-Fe-S significantly improved diversity and composition of microbial community, especially increasing the relative abundance of heavy metal-resistant bacteria. Overall, these results suggested BC-Fe-S as a high-performance and environmental-friendly amendment with stability to remediate heavy metals polluted soil.

通过同时负载Fe ₂ O _{3设计了硫铁功能化生物炭（BC-Fe-S）}纳米颗粒并将含硫官能团接枝到生物炭上以稳定土壤中的铅和镉。BC-Fe-S 对 Pb 和 Cd 表现出优异的稳定性能，在 5 天内具有快速的动力学平衡，与准二级模型相关。修复20天后，3% BC-Fe-S处理后生物有效铅和镉含量分别降低了59.22%和70.28%。形态转化分析表明，随着土壤水分和pH适宜，稳定时间和BC-Fe-S用量的增加促进了Pb和Cd的毒性随着不稳定组分向更稳定组分的转变而降低。3% BC-Fe-S处理后Pb和Cd的不稳定组分分别下降了12.22%和16.21%，并转变为残留形态。同时，干湿和冻融老化并没有显着改变铅和镉的生物利用度，证明 BC-Fe-S 有望在不同的环境条件下稳定铅和镉。16 S rRNA测序分析表明，BC-Fe-S显着改善了微生物群落的多样性和组成，尤其是增加了耐重金属细菌的相对丰度。总体而言，这些结果表明 BC-Fe-S 作为一种高性能和环保的改良剂，具有修复重金属污染土壤的稳定性。