Development of oxygen vacancies enriched CoAl hydroxide@hydroxysulfide hollow flowers for peroxymonosulfate activation: A highly efficient singlet oxygen-dominated oxidation process for sulfamethoxazole degradation
Development of oxygen vacancies enriched CoAl hydroxide@hydroxysulfide hollow flowers for peroxymonosulfate activation: A highly efficient singlet oxygen-dominated oxidation process for sulfamethoxazole degradation
复制标题
开发氧空位富集的氢氧化钴@羟基硫化物空心花用于过一硫酸盐活化：一种高效的单线态氧主导的磺胺甲恶唑降解氧化过程
DOI：
10.1016/j.jhazmat.2020.123297
复制
发表时间：
2020
影响因子：
13.6
通讯作者：
Shi Zhou
中科院分区：
文献类型：
--
作者：
Zeng Hanxuan;Deng Lin;Zhang Haojie;Zhou Chan;Shi Zhou
本研究采用硫化钠溶液原位刻蚀法制备了富氧缺位氢氧化铝钴@羟基硫化物(Coal-LDH@CoSx)中空花。用扫描电子显微镜、能谱仪、X射线衍射仪和X射线光电子能谱对样品进行了表征。合成的0.2CoAl-LDH@CoSx对PMS活化降解磺胺甲恶唑(SMX)表现出比原煤LDH更高的催化性能。用0.1g/L、0.2CoAl-LDH@CoSx和0.3mMPMS在pH 6.0条件下处理4min，可去除98.5%的SMX(40亩M)。降解符合准一级反应动力学，0.2CoAl-LDH@CoSx/PMS体系的降解速率常数为0.89min(-1)，煤-LDH/PMS体系的降解速率常数为0.55min(-1)。通过猝灭实验证实，单线态氧(O-1(2))是降解SMX的主要活性氧物种。机理研究表明，0.2CoAl-LDH@CoSx表面的氧空位、Co(II)/Co(III)和S-2(2-)/(S2-和硫酸盐物种)的氧化还原循环是PMS活化的关键。此外，通过对SMX降解中间体的分析，提出了SMX可能的降解途径。本研究不仅揭示了0.2CoAl-LDH@CoSx是活化PMS降解SMX的有效催化剂，而且为开发具有氧空位的多相催化剂提供了新的思路。
In this study, oxygen vacancies enriched cobalt aluminum hydroxide@hydroxysulfide (CoAl-LDH@CoSx) hollow flowers was synthesized by in-situ etching of CoAl-LDH using sodium sulfide solution. The analysis of SEM, EDS, XRD, and XPS were used to characterize the samples. The as-synthesized 0.2CoAl-LDH@CoSx displayed higher catalysis performance of sulfamethoxazole (SMX) degradation via the activation of PMS than the pristine CoAl-LDH. 98.5 % of SMX (40 mu M) was eliminated with 0.1 g/L 0.2CoAl-LDH@CoSx and 0.3 mM PMS at pH 6.0 in 4 min. The degradation fitted with the pseudo-first-order reaction kinetics well with rate constant of 0.89 min(-1) for 0.2CoAl-LDH@CoSx/PMS system and 0.55 min(-1) for CoAl-LDH/PMS system. Singlet oxygen (O-1(2)) was verified as dominant reactive oxygen species responsible for SMX degradation via quenching tests. Mechanism investigation suggested that the oxygen vacancies, redox cycles of Co(II)/Co(III) and S-2(2-)/(S2- and sulfate species) on the surface of 0.2CoAl-LDH@CoSx were crucial for PMS activation. In addition, the plausible degradation pathways of SMX were proposed by analysis of the SMX degradation intermediates. This study not only reveals that 0.2CoAl-LDH@CoSx is an efficient catalyst to activate PMS for SMX degradation, but also shed a novel insight into development of heterogeneous catalysts with oxygen vacancies.