Biogenic ferrous sulfide nanoparticles (bio-FeS) as low-cost and green-synthesized nanomaterial are promising for heavy metals removal, but the need for complicated extraction, storage processes and the production of iron sludge still restrict their practical application. Here, a self-regenerable bio-hybrid consisting of bacterial cells and self-assembled bio-FeS was developed to efficiently remove chromium (Cr(VI)). A dense layer of bio-FeS was distributed on the cell surface and in the periplasmic space of Shewanella oneidensis MR-1, endowing the bacterium with good Cr(VI) tolerance and unusual activity for bio-FeS-mediated Cr(VI) reduction. An artificial transmembrane electron channel was constituted by the bio-FeS to facilitate extracellular electron pumping, enabling efficient regeneration of extracellular bio-FeS for continuous Cr(VI) reduction. The bio-hybrid maintained high activity within three consecutive treatment-regeneration cycles for treating both simulated Cr(VI)-containing wastewater (50 mg/L) and real electroplating wastewater. Importantly, its activity can be facilely and fully restored through bio-FeS re-synthesis or regeneration with replenished fresh bacteria. Overall, the bio-hybrid merges the self-regeneration ability of bacteria with high activity of bio-FeS , opening a promising new avenue for sustainable treatment of heavy metal- containing wastewater.

生物硫化亚铁纳米颗粒（bio-FeS）作为一种低成本、绿色合成的纳米材料，有望用于去除重金属，但复杂的提取、储存过程和铁泥生产的需要仍然限制了它们的实际应用。在这里，开发了一种由细菌细胞和自组装生物 FeS 组成的可自我再生的生物混合物，以有效去除铬（Cr（VI））。Shewanella oneidensis的细胞表面和周质空间分布着一层致密的生物FeSMR-1，赋予细菌良好的 Cr(VI) 耐受性和非同寻常的生物 FeS 介导的 Cr(VI) 还原活性。生物 FeS 构成了人工跨膜电子通道，以促进细胞外电子泵浦，使细胞外生物 FeS 有效再生，从而连续还原 Cr(VI)。在处理模拟含 Cr(VI) 废水 (50 mg/L) 和实际电镀废水的三个连续处理-再生循环中，生物混合物保持高活性。重要的是，它的活性可以通过生物 FeS 再合成或用补充的新鲜细菌再生来轻松和完全恢复。总体而言，生物杂交结合了细菌的自我再生能力和 bio-FeS 的高活性，