Biochar currently served as the support for dispersed metal nanoparticles and cooperated with pyrite to generate more reactive radicals in organic pollution degradation system. But the mechanism of interaction between biochar and pyrite has not been elucidated. In this paper, biochar with oxygen-containing functional groups (OFGs) served as a stable dispersant to prepare nano-Fe_xS_y loaded biochar materials (BC_OFGs@nano-Fe_xS_y). BC_OFGs coordinated with nano-Fe_xS_y to overcome its drawbacks, boosting QNC removal efficiency from 28.64% to 100%. The XPS and the linear sweep voltammetry (LSV) results revealed higher Fe(II) content and higher electron transfer rate on used BC_OFGs@nano-Fe_xS_y, further validating that hydroxyl functional groups on biochar surface provided electrons to Fe(III) to achieve efficient Fe(II)/Fe(III) cycling. Based on comparative experiments and studies on the roles of iron, S(II) species and OFGs, we clearly revealed that OFGs on biochar materials surface coordinated with nano-Fe_xS_y to catalyze the degradation of QNC. The degradation efficiency of BC_OFGs@nano-Fe_xS_y for QNC was still as high as 91.39% after five cycles, providing full demonstrations that OFGs and S(II) as the abundant electron donor coordinated with Fe species for QNC catalytic degradation and further enhanced the catalytic performance and stability of nano-Fe_xS_y.

生物炭目前作为分散金属纳米粒子的载体，与黄铁矿配合，在有机污染降解系统中产生更多的活性自由基。但生物炭与黄铁矿相互作用的机制尚未阐明。在本文中，具有含氧官能团的生物炭（OFGs）作为一种稳定的分散剂来制备纳米Fe _x S _y负载生物炭材料（BC _OFGs @nano-Fe _x S _y）。BC _OFGs与 nano-Fe _x S _y协调为了克服其缺点，将 QNC 去除效率从 28.64% 提高到 100%。_{XPS 和线性扫描伏安法 (LSV) 结果显示，在使用过的 BC OFG} @nano-Fe _x S _y上， Fe(II) 含量和电子转移率更高，进一步验证了生物炭表面上的羟基官能团为 Fe(III) 提供了电子) 以实现高效的 Fe(II)/Fe(III) 循环。基于对铁、S(II)物种和OFGs作用的比较实验和研究，我们清楚地揭示了生物炭材料表面的OFGs与纳米Fe _x S _y协同催化QNC的降解。_{BC OFGs} @nano-Fe _x S _y的降解效率五次循环后 QNC 的催化降解率仍高达 91.39%，充分证明 OFGs 和 S(II) 作为丰富的电子供体与 Fe 物种配位用于 QNC 催化降解，进一步提高了纳米 Fe _x S的催化性能和稳定性_是的。