Barabás Júlia, Ferrari Piero, Kaydashev Vladimir, Vanbuel Jan, Janssens Ewald, Höltzl Tibor
Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics 1111 Budapest Hungary.
Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven 3001 Leuven Belgium
RSC Adv. 2021 Sep 1;11(47):29186-29195. doi: 10.1039/d1ra03262c.
The catalytic activity of metal clusters can be easily tuned by their size, charge state, or the introduction of dopant atoms. Here, the dopant-, charge- and size-dependent propene adsorption on gold (Au ) and yttrium doped gold (Au Y) clusters ( = 4-20) was investigated using combined gas-phase reaction studies and density functional theory computations. The increased charge transfer between the cluster and propene in the cationic clusters considerably enhances the propene binding on both pure and yttrium-doped species, compared to their neutral cluster counterparts, while yttrium-doping lowers the propene binding strength in a size-dependent way compared to the pure gold clusters. Chemical bonding and energy decomposition analysis indicate that there is no covalent bond between the cluster and propene. The preferred propene binding site on a cluster is indicated by the large lobes of its LUMO, together with the low coordination number of the adsorption site. In small yttrium-doped gold clusters propene can not only bind to the electron-deficient yttrium atom, but also to the partially positively-charged gold atoms. Therefore, by controlling the charge of the clusters, as well as by introducing yttrium dopants, the propene binding strength can be tuned, opening the route for new catalytic applications.
金属团簇的催化活性可通过其尺寸、电荷状态或掺杂原子的引入而轻易调节。在此，利用气相反应研究与密度泛函理论计算相结合的方法，研究了掺杂剂、电荷和尺寸对丙烯在金（Au ）和钇掺杂金（Au Y）团簇（ = 4 - 20）上吸附的影响。与中性团簇相比，阳离子团簇中团簇与丙烯之间电荷转移的增加显著增强了丙烯在纯金和钇掺杂物种上的结合，而与纯金团簇相比，钇掺杂以尺寸依赖的方式降低了丙烯的结合强度。化学键合和能量分解分析表明，团簇与丙烯之间不存在共价键。团簇上丙烯的优先结合位点由其最低未占分子轨道的大瓣以及吸附位点的低配位数表明。在小的钇掺杂金团簇中，丙烯不仅可以与缺电子的钇原子结合，还可以与部分带正电的金原子结合。因此，通过控制团簇的电荷以及引入钇掺杂剂，可以调节丙烯的结合强度，为新的催化应用开辟了道路。
