Selective and efficient removal of trace heavy metals from drinking water has been a challenging problem. Herein, we report novel activated carbon fibers rich in S/N/O multiple active sites (ACF-S/N/O) obtained by hydrogen peroxide pretreatment and 2,5-dimercapto-1,3,4-thiadiazole (DMTD) post-functionalization. The coexistence of -SH, =N-, -NH-, -NH₂, -COOH and -OH functional groups in ACF-S/N/O greatly increased adsorption performance and selectivity for trace lead. The adsorbent prepared at optimum nominal mass ratio (9:11) of ACFs pretreated by hydrogen peroxide (ACF-O) to DMTD represented excellent and selective adsorption behavior for trace lead, and maximum adsorption capacity which effluent concentration met World Health Organization (WHO) standard attained 29.05 mg g⁻¹, which was far above those of previously reported materials. Moreover, the adsorbent also exhibited rapid adsorption dynamics, superior selectivity for trace lead, and excellent adsorption performance under broad pH and concentration range, as well as in tap water. The adsorption data were well fitted to Freundlich and D-R isotherm models and pseudo-second-order kinetic model, respectively, suggesting chemical adsorption mechanism. The abundant S/N/O active sites greatly overcame mass transfer resistance of trace lead and promoted the chelation between the adsorption site and trace lead, making adsorbent exhibit excellent application prospects for drinking water purification.

选择性和有效地去除饮用水中的痕量重金属一直是一个具有挑战性的问题。在此，我们报告了通过过氧化氢预处理和 2,5-二巯基-1,3,4-噻二唑 (DMTD) 后获得的富含 S/N/O 多活性位点 (ACF-S/N/O) 的新型活性炭纤维-功能化。ACF-S/N/O中-SH、=N-、-NH-、-NH ₂ 、-COOH和-OH官能团的共存大大提高了对痕量铅的吸附性能和选择性。以最佳标称质量比 (9:11) 的过氧化氢 (ACF-O) 预处理的 ACF 与 DMTD 制备的吸附剂对痕量铅具有优异的选择性吸附行为，并具有最大的吸附容量符合世界卫生组织 (WHO) 标准的出水浓度达到 29.05 mg g ^-1，远高于先前报道的材料。此外，该吸附剂还表现出快速的吸附动力学、对痕量铅的优异选择性，以及在广泛的 pH 值和浓度范围以及自来水中的优异吸附性能。吸附数据分别很好地拟合了 Freundlich 和 DR 等温线模型和准二级动力学模型，表明了化学吸附机理。丰富的S/N/O活性位点极大地克服了微量铅的传质阻力，促进了吸附位点与微量铅的螯合，使吸附剂在饮用水净化中展现出极好的应用前景。