Orientation of acetic acid hydrogen bonded to acetate terminated TiO2(110)
Orientation of acetic acid hydrogen bonded to acetate terminated TiO2(110)
复制标题
DOI：
10.1016/j.susc.2020.121628
复制
发表时间：
2020-09-01
期刊：
影响因子：
1.9
通讯作者：
Thornton, Geoff
中科院分区：
文献类型：
--
作者：
Dover, Coinneach Mackenzie;Grinter, David C.;Thornton, Geoff
乙酸是一种常见的污染物，二氧化钛上的光催化降解提供了一种缓解策略。需要了解乙酸盐/乙酸与该基材的键合，以帮助解释光催化数据。在这项工作中，我们使用环境压力近边缘 X 射线吸收精细结构来测量 TiO2(110) 接触层中乙酸盐以及附加层中乙酸盐的覆盖率和几何形状。在 266 K 下，乙酸压力高达 10(-1) Torr 时，两层中的饱和覆盖度均为 0.5 个单分子层。乙酸盐的几何形状似乎不会因吸附额外的乙酸层而改变，其中接触层涉及与相邻 Ti-5c 位点键合的大部分乙酸盐物质双齿和以垂直几何形状键合的少数乙酸盐物质。乙酸具有由与接触层和基材的氢键键合决定的相似几何形状。
Acetic acid is a common pollutant for which photocatalytic degradation over titania provides a mitigating strategy. Knowledge of the bonding of acetate/acetic acid to this substrate is needed to aid interpretation of the photocatalytic data. In this work we use ambient pressure near edge X-ray absorption fine structure to measure the coverage and geometry of acetate in the TiO2(110) contact layer as well as acetic acid in an additional layer. A saturation coverage of 0.5 monolayers in both layers is found up to an acetic acid pressure of 10(-1) Torr at 266 K. The geometry of acetate appears to be unchanged by adsorption of an additional layer of acetic acid, with the contact layer involving a majority acetate species bidentate bonded to neighboring Ti-5c sites and a minority acetate species bonded in a perpendicular geometry. Acetic acid has a similar geometry dictated by hydrogen bonding to the contact layer as well as the substrate.