Faculty of Chemistry, Hanoi National University of Education, 100000, 136 Xuan Thuy Str., Hanoi, Viet Nam.
J Mol Graph Model. 2021 Sep;107:107979. doi: 10.1016/j.jmgm.2021.107979. Epub 2021 Jun 26.
A combination of Artificial Bee Colony algorithm, eXtended Tight Binding and Density functional theory methods were performed to study the activation process of carbon dioxide (CO) over copper (Cu cluster) based catalytic systems. The findings revealed that the activation of the C-O bond resulted from the electron transfer to σ*, π* - MO of CO. The more the electrons are transferred to CO, the more the C-O bond is activated and elongated. The suitability of several metal oxide supports (FeO, AlO, MgO, ZnO) is estimated using calculated electronic parameters (global electrophilicity index, vertical ionization potential and vertical electron affinity). Aside from demonstrating the appropriateness of AlO and ZnO, a thorough examination of MgO revealed that, due to the formation of stable carbonate products, this oxide is not really appropriate as a support for copper-based catalysts in CO conversion. Our studies have also shown that the electron enrichment of copper atoms plays a key role in the activation of C-O bonds. Alkali metal doping (Li, K, Cs) significantly improves the catalytic efficiency of the Cu cluster. Based on the results of electron transfer to the CO molecule, the effect of doping alkali metal atoms may be organized in the following order: Cs > K > Li. A new core/shell catalytic system with potassium atoms in the core and copper atoms in the shell has been proposed and has proven to be a promising, efficient catalytic system in the CO adsorption and activation.
采用人工蜂群算法、扩展紧束缚和密度泛函理论方法，研究了二氧化碳（CO）在基于铜（Cu 团簇）的催化体系中的活化过程。研究结果表明，C-O 键的活化是由于电子转移到 CO 的 σ*、π* - MO。转移到 CO 的电子越多，C-O 键的活化和伸长就越多。利用计算得到的电子参数（全球电亲性指数、垂直电离势和垂直电子亲合势）来估计几种金属氧化物载体（FeO、AlO、MgO、ZnO）的适用性。除了证明 AlO 和 ZnO 的适宜性外，对 MgO 的深入研究表明，由于形成稳定的碳酸盐产物，这种氧化物作为 CO 转化中铜基催化剂的载体并不合适。我们的研究还表明，铜原子的电子富集在 C-O 键的活化中起着关键作用。碱金属掺杂（Li、K、Cs）显著提高了 Cu 团簇的催化效率。基于向 CO 分子转移电子的结果，掺杂碱金属原子的效果可以按以下顺序排列：Cs>K>Li。提出了一种具有钾原子为核、铜原子为壳的新型核/壳催化体系，该体系在 CO 吸附和活化方面表现出良好的催化效果。
