Cappellari Paula S, Soldano Germán J, Mariscal Marcelo M
INFIQC, CONICET, Departamento de Qumíca Teórica y Computacional, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba (XUA5000) Córdoba Argentina
RSC Adv. 2018 Mar 14;8(19):10450-10456. doi: 10.1039/c7ra13347b. eCollection 2018 Mar 13.
IrAu nanoalloys have been proven to have remarkable reactivity for several reactions. In this work, mixed IrAu nanoalloys of 8, 27, 48 and 64 total atoms were studied in different atomic compositions (Ir Au ) using Density Functional Theory (DFT). A notable segregation tendency is observed, where Ir atoms are located in the inner part and Au atoms in the outermost region of the nanostructure. We found that IrAu nanoalloys present a distinctive synergistic effect with respect to reactivity. In addition, the projected density of electronic states (PDOS) energies were analyzed by examining the d-band shift to estimate the reactivity of various IrAu nanoalloys. Furthermore, the adsorption energies for the CO molecule in the domains of the Ir-Au interface were evaluated. In this sense, the addition of Au atoms to Ir clusters increases the reactivity of Ir by generating unoccupied orbitals near the Fermi level as indicated by the PDOS study.
铱金纳米合金已被证明对多种反应具有显著的反应活性。在这项工作中，使用密度泛函理论（DFT）研究了总原子数为8、27、48和64的不同原子组成（Ir Au ）的混合铱金纳米合金。观察到一种显著的偏析趋势，其中铱原子位于纳米结构的内部，金原子位于最外层区域。我们发现铱金纳米合金在反应活性方面呈现出独特的协同效应。此外，通过检查d带位移来分析电子态投影密度（PDOS）能量，以估计各种铱金纳米合金的反应活性。此外，还评估了Ir - Au界面区域中CO分子的吸附能。从这个意义上说，如PDOS研究所表明的，向铱团簇中添加金原子通过在费米能级附近产生未占据轨道来提高铱的反应活性。
