Electron Donation from Cu Atoms to Al Oxide Clusters upon Mixing Revealed by Thermal Desorption Spectrometry
Electron Donation from Cu Atoms to Al Oxide Clusters upon Mixing Revealed by Thermal Desorption Spectrometry
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热解吸光谱法揭示了混合时铜原子向氧化铝簇的电子供给
DOI：
10.1021/acs.jpcc.9b09682
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Kudoh Satoshi
中科院分区：
文献类型：
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作者：
Mafune Fumitaka;Zhang Yufei;Liu Xinan;Wang Haohao;Kudoh Satoshi
众所周知，铜原子的反应性对其荷电状态很敏感。基于气相热脱附谱(TDS)和密度泛函理论(DFT)计算，在原子水平上讨论了Al_4O_6~+和Al_4O_7~+与铜原子混合的电荷态。通过实验比较耐热的铜/铝氧化物团簇离子和铝氧化物团簇离子的组成，发现在Al_4O_6+和Al_4O_7+中加入三个铜原子和稳定的Al_2O_3团簇伴随着一个额外的O原子，即在Al_4O_6+和Al_4O_7+中加入Cu3O(而不是Cu3O或Cu3O_3)。通过密度泛函理论计算，得到了稳定的Al4O6+、Al4O7+、Cu3Al4O7+和Cu3Al4O8+的几何异构体。几何构型和原子上电荷分布的分析表明，具有相同组成的低能异构体具有基本相似的局域结构和电荷分布。因此，我们认为团簇的稳定性是由原子的局域结构和电荷分布决定的。当铜原子与氧化铝团簇混合时，铜原子可以提供电子给缺电子的O原子，并成为正电荷。
It is well-known that the reactivity of a Cu atom is sensitive to its charge state. We discussed the charge states of the Cu atoms mixed with Al oxide clusters (Al4O6+and Al4O7+) at an atomic level based on gas-phase thermal desorption spectrometry (TDS) and density functional theory (DFT) calculations. By comparing the compositions of thermally durable Cu/Al oxide cluster ions with those of Al oxide cluster ions experimentally, it was found that mixing three Cu atoms with the stable Al oxide clusters accompanied one additional O atom, and namely, Cu3O (and not Cu3or Cu3O3) was added to Al4O6+and Al4O7+. Stable geometrical isomers were obtained for Al4O6+, Al4O7+, Cu3Al4O7+, and Cu3Al4O8+by DFT calculations. Analysis of the geometries and the charge distributions on the atoms indicates that the low-energy isomers with the same compositions have essentially similar local structures and charge distributions. Hence, it is considered that the stability of the clusters is determined by the local structure and the charge distribution on the atoms. When the Cu atoms are mixed with the Al oxide clusters, the Cu atoms can afford to donate electrons to the electron-deficient O atoms and become positively charged.