KBH4 Modification of Fe3O4 Core Shell Carbon Microspheres Promoted Persulfate Activation for Organic Contaminants degradation: Factors and Mechanism
KBH4 Modification of Fe3O4 Core Shell Carbon Microspheres Promoted Persulfate Activation for Organic Contaminants degradation: Factors and Mechanism
复制标题
Fe3O4核壳碳微球的KBH4改性促进过硫酸盐活化降解有机污染物：因素和机制
DOI：
10.1007/s10562-022-04143-8
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发表时间：
2022
影响因子：
2.8
通讯作者：
Ma Zhifei
中科院分区：
文献类型：
--
作者：
Zian Cheng;Huiyu Tao;Ji Zhang;Shuaima Wang;Yu Yang;Jianlong Li;Daishe Wu;Ma Zhifei
本研究开发了一种两步法，通过木糖氯化铁和尿素的水热碳化和硼氢化钾（KBH4）还原方法制备氮掺杂碳微球包覆的Fe3O4。所获得的材料（Fe3O4@C-BH）促进了过硫酸盐（PS）的活化以降解有机污染物。通过系统表征，证实纳米 Fe3O4 颗粒被封装在碳球中。凭借碳涂层的保护作用，改善了Fe3O4易团聚、氧化的问题。 Fe3O4@C-BH 具有有效的催化性能，可以激活 PS 来降解 RB5。 RB5的去除率和矿化率分别为95.8%和65%。初始溶液的pH值和无机阴离子（Cl−和SO42−）对活性黑5（RB5）的降解影响很小。此外，它对刚果红 (CR)、罗丹明 B (RhB) 和盐酸四环素 (TC) 具有很高的去除效率。值得注意的是，KHB4改性增加了碳表面的氧官能团和Fe2+含量，被认为是提高催化活性的主要原因。通过电子顺磁共振（EPR）和猝灭实验分析，SO4⋅−、⋅OH和1O2是氧化过程中的主要活性物质。提出了一种合理的机制，其中封装的 Fe3O4 纳米、氧官能团和掺杂的氮协同驱动 PS 活化以去除有机污染物。它为开发高效核壳碳基材料作为 PS 活化剂以降解地下水中的有机污染物提供了新的见解。图形摘要
This study developed a two-step method to prepare nitrogen-doped carbon microsphere-coated Fe3O4 by hydrothermal carbonization and potassium borohydride (KBH4) reduction methods deriving from xylose ferric chloride and urea. The obtained material (Fe3O4@C-BH) promoted the persulfate (PS) activation for degradation of organic contaminants. The nano-Fe3O4 particles were confirmed to be encapsulated in carbon spheres by systematic characterization. In virtue of the protective effect of carbon coating, the problems of being prone to agglomeration and oxidation of Fe3O4 were improved. Fe3O4@C-BH featured the effective catalytic performance to activate PS for RB5 degradation. The removal and mineralization rates of RB5 were 95.8% and 65%, respectively. The pH of the initial solution and the inorganic anions (Cl− and SO42−) had little effect on the degradation of reactive black 5 (RB5). Further, it performed high removal efficiency for Congo Red (CR), Rhodamine B (RhB) and tetracycline hydrochloride (TC). Notably, the increase of oxygen functional groups and Fe2+ content on the carbon surface by KHB4 modification was considered to be the main reason for improving catalytic activity. By analyzing electron paramagnetic resonance (EPR) and quenching experiments, SO4⋅−, ⋅OH and 1O2 were the primary active substances in oxidation process. A plausible mechanism was proposed in which the encapsulated Fe3O4 nano, oxygen functional groups and doped nitrogen synergistically drove PS activation to remove organic contaminants. It provides new insights into developing efficient core–shell carbon-based materials as PS activators for organic contaminants degradation in groundwater.Graphical Abstract