摘要
A previous study showed that TiO 2-B (100) surface is very unique. It is characterised by high activity and a loose structure. In this study, we studied the adsorption of ammonia on TiO 2-B (100) surface at coverages ranging from 1/6 ML to 1 ML using ab initio density functional calculations. We also investigated the adsorption of an isolated ammonia molecule on TiO 2-B (001) surface to compare the different activities of TiO 2-B (100) and (001) surfaces towards NH 3. The results showed that the TiO 2-B (100) surface is more reactive towards NH 3 molecule than TiO 2-B (001) surface, and the Lewis acid site on TiO 2-B (100) surface is more acidic. The decrease rate of the average molecular adsorption energy of NH 3 with coverage on TiO 2-B (100) surface is substantially lower than that on a rutile (011) surface above 1/2 ML coverage due to the open structure of TiO 2-B (100) surface. The average molecular adsorption energy shows a linear dependence on the coverage of y = 111.0 - 36.3x on TiO 2-B (100) surface. The possibility of NH 3 molecule onto the Ti 5c site is nearly equal to forming a dimer with adsorbed NH 3 on TiO 2-B (100) surface at 5/6 ML coverage.
源语言 | 英语 |
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页(从-至) | 16618-16625 |
页数 | 8 |
期刊 | Physical Chemistry Chemical Physics |
卷 | 14 |
期 | 48 |
DOI | |
出版状态 | 已出版 - 28 12月 2012 |