Gomes Alexandre C R, de Souza Tiago M, Da Silva Juarez L F, Galvão Breno R L
Departamento de Química, Centro Federal de Educação Tecnológica de Minas Gerais, CEFET-MG, Av. Amazonas 5253, (30421-169) Belo Horizonte, Minas Gerais, Brazil.
Phys Chem Chem Phys. 2020 Nov 14;22(42):24669-24676. doi: 10.1039/d0cp02974b. Epub 2020 Oct 26.
The potential of doped aluminium clusters as catalysts for the water splitting reaction has attracted considerable scientific effort, however, the water-cluster interactions, which are a key step in the overall mechanism, are not fully understood. Here, we report an ab initio investigation of water adsorption on AlSi clusters at the MP2 level to elucidate the bonding and structural properties employing unary and binary 8- and 13-atom clusters, namely, Si, AlSi, AlSi, Al, Si, AlSi, AlSi, and Al, which were selected by their relevance and energetic stability. We found that HO binds via the O atom near to the on-top sites of the Si or Al atoms; in particular, there is a strong preference for the Al sites on the binary AlSi clusters, which is supported by the strong adsorption energy. Furthermore, we found a large enhancement of the adsorption energy on the AlSi and AlSi clusters, which can be explained by the cationic character of the Al site, which increases the Coulomb contribution to the Al-O interaction.
掺杂铝簇作为水分解反应催化剂的潜力已经吸引了大量的科学研究，但作为整个反应机理关键步骤的水簇相互作用尚未完全明确。在此，我们报告了在MP2水平上对水在AlSi簇上吸附的从头算研究，以阐明其键合和结构性质，研究采用了一元和二元的8原子及13原子簇，即Si、AlSi、AlSi、Al、Si、AlSi、AlSi和Al，这些簇是根据其相关性和能量稳定性选择的。我们发现HO通过靠近Si或Al原子顶位的O原子进行键合；特别是，二元AlSi簇对Al位点有很强的偏好，这一点得到了强吸附能的支持。此外，我们发现AlSi和AlSi簇上的吸附能有大幅增强，这可以用Al位点的阳离子特性来解释，该特性增加了对Al-O相互作用的库仑贡献。
