Zhao Lele, Zhang Jiaming, Zhang Zhiping, Wei Tong, Wang Jun, Ma Jun, Ren Yueming, Zhang Hexin
Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China.
School of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China.
J Colloid Interface Sci. 2022 Oct;623:520-531. doi: 10.1016/j.jcis.2022.05.045. Epub 2022 May 13.
Crystal plane effect has attracted remarkable attention in the process of peroxymonosulfate (PMS) activation in water. In this work, nanocube-CoO (CoO-NC), nanoplate-CoO (CoO-NP) and nanorod-like CoO (CoO-NR) with (100), (111) and (110) plane predominant exposure is prepared by a facile hydrothermal method. CoO-NR with (110) plane exposed possesses more lattice defects (oxygen vacancies, Ov) and low oxidation state Co (Co), consequently, it exhibits a superior activity for PMS activation to efficiently remove bisphenol A (BPA) in water. Furthermore, it could be used in a widely water pH values ranging from 5.0 to 9.0 with an excellent PMS activited effects. During CoO-NR/PMS oxidation process, it is found that singlet oxygen (O) plays a dominant role in BPA degradation. However, CoO-NR treated by HO shows a poor PMS activation performance, confirming Ov acting as the active site during such oxidation process. The important effect of dissolved oxygen is tested by Ar introduction into the reaction system and the Ov-O* metastable intermediate is proposed. In situ Raman proves the interaction between dissolved oxygen and Ov and then the intermediate activates PMS to degrade BPA. This work not only explores the effect of different crystal plane exposures on PMS activation in CoO/PMS system, but investigates the evolution of Ov during the PMS activation.
在水中过一硫酸盐（PMS）活化过程中，晶面效应引起了广泛关注。在本工作中，通过简便的水热法制备了以（100）、（111）和（110）面为主暴露面的纳米立方CoO（CoO-NC）、纳米片CoO（CoO-NP）和纳米棒状CoO（CoO-NR）。具有（110）面暴露的CoO-NR具有更多的晶格缺陷（氧空位，Ov）和低价态Co（Co），因此，它对PMS活化表现出优异的活性，能有效去除水中的双酚A（BPA）。此外，它可在5.0至9.0的广泛水pH值范围内使用，具有优异的PMS活化效果。在CoO-NR/PMS氧化过程中，发现单线态氧（O）在BPA降解中起主导作用。然而，经HO处理的CoO-NR表现出较差的PMS活化性能，证实Ov在此类氧化过程中作为活性位点。通过向反应体系中引入Ar测试了溶解氧的重要作用，并提出了Ov-O*亚稳中间体。原位拉曼光谱证明了溶解氧与Ov之间的相互作用，然后该中间体活化PMS以降解BPA。这项工作不仅探索了不同晶面暴露对CoO/PMS体系中PMS活化的影响，还研究了PMS活化过程中Ov的演变。
