Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China; Chengdu Surveying Geotechnical Research Institute Co., Ltd. of MCC, Sichuan 610023, PR China.
Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, PR China.
Sci Total Environ. 2022 May 1;819:152787. doi: 10.1016/j.scitotenv.2021.152787. Epub 2022 Jan 4.
In this work, the role of Fe in the synergetic effect of persulfate/sulfite and FeO@g-CN (FCN) for carbamazepine (CBZ) degradation was studied. Unexpectedly, FeO in FCN plays very different roles for sulfite [S(IV)] and persulfate (PS) activation. Specifically, since photo-generated holes (h) can transform S(IV) into SO, and photo-generated electrons (e) can accelerate Fe(III) reduction which promotes transition metal based S(IV) activation, a synergetic effect of photocatalysis and Fe is observed in FCN/S(IV)/vis system. In contrast, in FCN/PS/vis system, both Fe(III)/Fe(II) cycle and PS activation compete for e. Since PS is a stronger electron acceptor, Fe(III) reduction by e is limited. Therefore, the contribution of FeO in FCN/S(IV)/vis system is 3 times higher than that in FCN/PS/vis system. Initial pH affects CBZ removal by changing surface charge of catalysts and oxidants species, while the effect varies for different catalysts and oxidants. This study provides new insight into the synergetic effect of photocatalysis and transition metal for SO generation, which contributes to catalyst design for environmental application.
在这项工作中，研究了铁在过硫酸盐/亚硫酸盐和 FeO@g-CN（FCN）协同作用降解卡马西平（CBZ）中的作用。出乎意料的是，FCN 中的 FeO 对亚硫酸盐[S(IV)]和过硫酸盐（PS）的活化起着非常不同的作用。具体来说，由于光生空穴（h）可以将 S(IV)转化为 SO，并且光生电子（e）可以加速促进基于过渡金属的 S(IV)活化的 Fe(III)还原，因此在 FCN/S(IV)/可见光系统中观察到光催化和 Fe 的协同作用。相比之下，在 FCN/PS/可见光系统中，Fe(III)/Fe(II)循环和 PS 活化都争夺 e。由于 PS 是更强的电子受体，因此 e 对 Fe(III)的还原受到限制。因此，FCN/S(IV)/可见光系统中 FeO 的贡献比 FCN/PS/可见光系统高 3 倍。初始 pH 通过改变催化剂和氧化剂物种的表面电荷来影响 CBZ 的去除，而不同催化剂和氧化剂的影响则不同。本研究为光催化和过渡金属协同生成 SO 提供了新的见解，这有助于环境应用中的催化剂设计。
