Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6133, USA.
Chemical Science Division and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
Sci Rep. 2017 Jul 24;7(1):6231. doi: 10.1038/s41598-017-06405-7.
The ab initio density functional theoretical studies show that energetics favor CO oxidation on single Pd atoms supported on θ-alumina. The diffuse reflectance infra-red spectroscopy (DRIFTS) results show that carbonates are formed as intermediates when single supported Pd atoms are exposed to a gaseous mixture of CO + O. The rapid agglomeration of Pd atoms under CO oxidation conditions even at 6 °C leads to the presence of Pd particles along with single atoms during CO oxidation experiments. Thus, the observed CO oxidation has contributions from both single Pd atoms and Pd particles.
从头算密度泛函理论研究表明，热力学有利于 CO 在负载于θ-氧化铝上的单个 Pd 原子上的氧化。漫反射红外光谱（DRIFTS）结果表明，当单个负载的 Pd 原子暴露于 CO+O 的混合气体中时，形成了碳酸盐中间体。在 CO 氧化条件下，即使在 6°C 下，Pd 原子也会迅速团聚，导致在 CO 氧化实验中存在 Pd 颗粒和单个原子。因此，观察到的 CO 氧化既来自于单个 Pd 原子，也来自于 Pd 颗粒。
