| 查看: 842 | 回复: 0 | |||
[交流]
采用同位素标记法探测TiO2光催化体系水相降解苯环开环机理
|
|
中科院北京化学所 赵进才 院士 最近JACS ——采用同位素标记法探测TiO2光催化体系水相降解苯环开环机理 Determining the TiO2‑Photocatalytic Aryl-Ring-Opening Mechanism in Aqueous Solution Using Oxygen-18 Labeled O2 and H2O 采用同位素标记O2，H2O，一对叔丁基邻苯二酚为模型，在TiO2，水：乙腈=1:1比例溶剂中，研究芳香环开环产物。 首次获得了分子氧O2中O原子插入苯环C-C键的直接证据。这说明了分子氧O2是芳香烃开环的反应剂。 The molecules O2 and H2O dominate the cleavage of aromatic sp2 C −C bonds, a crucial step in the degradation of aromatic pollutants in aqueous TiO2 photocatalysis, but their precise roles in this process have remained elusive. This can be attributed to the complex oxidative species involved and to a lack of available models for reactions with a high yield of direct products. Here, we used oxygen-18 isotope labeled O2 and H2O to observe the aromatic ring-opening reaction of the model compound 3,5-di-tert-butylcatechol(DTBC), which was mediated by TiO2 photocatalysis in an aqueous acetonitrile solution. By analyzing the primary intermediate products ( ～75% yield), especially the seven-membered ring anhydrides that were formed, we obtained direct evidence for the oxygen atom of dioxygen insertion into a C −C bond of the aromatic ring. This indicates that molecular oxygen is the ultimate ring-opening agent in TiO2 photocatalysis and that it undergoes single O atom incorporation rather than the previously proposed molecular oxygen 1,2-addition processes. The ratio of intradiol to extradiol products depends on the particle size of TiO2 catalysts used, which suggests that the O2 activation is correlated with the available coordination sites on the TiO2 surface in the photocatalytic cleavage of the aromatic ring.  1.png  2.png  3.png  4.png |
回复此楼» 本帖附件资源列表
-
欢迎监督和反馈：小木虫仅提供交流平台，不对该内容负责。
本内容由用户自主发布，如果其内容涉及到知识产权问题，其责任在于用户本人，如对版权有异议，请联系邮箱：xiaomuchong@tal.com - 附件 1 : ja5031936.pdf
2015-03-12 15:06:03, 2.28 M
» 猜你喜欢
请问哪里可以代烧带压力的炉子？
已经有6人回复
-
关于合成MIL-125的求助
已经有0人回复
-
专业论文润色/翻译怎么收费?
已经有98人回复
-
双非本硕光催化方向想读博，请各位老师看看我！
已经有2人回复
-
瑞典林雪平大学范立洲课题组现招聘博士后、岗位制博士生
已经有0人回复
-
中国科大仿生界面材料科学全国重点实验室戴懿涛研究员/江雷院士团队招聘科研助理
已经有0人回复
-
中国科大仿生界面材料科学全国重点实验室戴懿涛研究员/江雷院士团队招聘科研助理
已经有0人回复
-
寻求物理化学学报最新的投稿模板！
已经有4人回复
-
东南大学杰青/海优团队招聘催化方向博士后
已经有866人回复
-
投稿咨询
已经有6人回复
-
自科面上 散金币 祈福
已经有60人回复
» 本主题相关商家推荐: (我也要在这里推广)
