| 铕掺杂对Co3O4活化过一硫酸盐降解亚甲基蓝性能的增强 |
| Co3O4 Doped with Europium as a Performance Enhanced Heterogeneous Catalyst to Activate Peroxymonosulfate for Degradation of Methylene Blue |
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| 摘要: 以Co （NO3）2和Eu （NO3）3为原料，采用草酸盐-热分解法制得了系列不同Co/Eu比例（nCo/nEu）的多孔双金属复合氧化物催化剂，并对其活化过一硫酸盐（PMS）降解亚甲基蓝（MB）的性能进行对比评价。结果表明，按nCo/nEu=9制得的材料（Co9Eu1）具有最为优异的活化PMS降解MB的性能。在温度为25℃、催化剂用量和PMS浓度分别为0.10 g·L-1和0.6 mmol·L-1的反应条件下，Co9Eu1/PMS体系对MB的降解率可达86.66%，而纯Co3O4催化下的MB降解率仅为52.62%。Co9Eu1出色的催化性能是由于Eu3+的缺电子特性增强了对吸附于催化剂表面PMS的极化而使其更易被主催化成分Co3O4活化。体系中阴离子C2O42-和HCO3-的存在对Co9Eu1/PMS氧化降解MB的性能具有明显抑制作用。猝灭实验和电子顺磁共振谱（EPR）证实Co9Eu1/PMS体系中同时存在SO4-·、·OH和·O2-三种自由基型活性物种以及1O2非自由基型活性物种，其中SO4-·对MB的氧化降解起关键作用。Co9Eu1具有良好的稳定性，在连续4次循环使用中其催化性能未见明显变化。 |
| 关键词: 路易斯酸 Co3O4 非均相催化 过一硫酸盐 亚甲基蓝 |
| 基金项目: 重庆市教委科技项目（No.KJQN202101102）和重庆理工大学科研项目（No.clgycx20203085，gzlcx20223170，gzlcx20223160）资助 |
| Abstract: Employing Co(NO3)2 and Eu(NO3)3 as raw materials, a series of porous Co/Eu bimetallic -oxide catalysts were synthesized through an oxalate-pyrolysis method, and their catalytic performances in activating peroxymonosulfate (PMS) for degradation of methylene blue (MB) were evaluated. The results showed that the sample with a Co/Eu molar ratio (nCo/nEu) of 9 (Co9Eu1) exhibited the most excellent catalytic property towards PMS decomposition for MB removal. The degradation ratio of MB was 86.66% in the system of Co9Eu1/PMS, while it was only 52.62% for the counterpart, under the reaction conditions:catalyst addition of 0.10 g·L-1, PMS concentration of 0.6 mmol·L-1, and a reaction temperature of 25℃. The outstanding catalytic performance of Co9Eu1 is attributed to the electron-deficient property of Eu3+, which can enhance the polarization of PMS adsorbed on the surface of the catalyst and then make PMS easier to be activated by the primary catalytic component of Co3O4. Meanwhile, it is found that both C2O42- and HCO3- anions have obvious inhibitory effects on the degradation efficiency of MB in the Co9Eu1/PMS reaction system. In addition, quenching experiments and electron paramagnetic resonance spectroscopies (EPR) identify that reactive oxygen species (SO4-·, ·OH and ·O2-) and non-radical reactive oxygen species (1O2) both exist in the reaction system. Among them, SO4-· plays a key role in MB oxidative degradation process. Furthermore, no significant changes in catalytic performance in four consecutive cycles was observed. |
| Keywords: Lewis acid Co3O4 heterogeneous catalysis peroxymonosulfate methylene blue |
| 投稿时间：2022-04-01 修订日期：2022-06-08 |
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| 夏强,廖小刚,沈海丽,郑林,李纲,沈俊.铕掺杂对Co3O4活化过一硫酸盐降解亚甲基蓝性能的增强[J].无机化学学报,2022,38(8):1567-1576. |
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