DFT Study of MoS2 and Hydrogen Adsorbed on the (1010) Face of MoS2
DFT Study of MoS2 and Hydrogen Adsorbed on the (1010) Face of MoS2
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DOI：
10.1039/b105048f
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发表时间：
2001-11
影响因子：
3.3
通讯作者：
V. Alexiev;R. Prins;T. Weber
中科院分区：
文献类型：
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作者：
V. Alexiev;R. Prins;T. Weber
采用DFT计算研究了MoS2催化重要(100)边缘的性质及其上氢的吸附。体相和表面的电子性质以及表面原子的弛豫位置通过两种不同的技术计算，即全电子和平面波赝势DFT方法。通过 (2×1) 表面池研究氢吸附，以解释 H-H 相互作用和吸附氢原子的不同构型。我们的计算表明，两种方法获得的电子结构和弛豫表面原子的位置是相同的，除了由于不同弛豫程序而导致的微小差异。 MoS2 的 (100) 表面包含由硫原子弛豫形成的弱耦合 S-S 对。氢吸附结果表明，氢吸附在硫对上，而不吸附在表面的Mo原子上。 (2×1) 电池上吸附的氢原子的可能构型中只有一种在能量上是有利的，而其他构型的能量相对于 H2 和 MoS2 的能量更高。
DFT calculations were employed to investigate the properties of the catalytically important (100) edge of MoS2 and the adsorption of hydrogen thereon. The electronic properties of the bulk and surface as well as the relaxed positions of surface atoms are calculated by two different techniques, namely all-electron and plane wave pseudo-potential DFT methods. Hydrogen adsorption is studied by means of a (2×1) surface cell to account for H–H interactions and the different configurations of adsorbed hydrogen atoms. Our calculations demonstrate that the electronic structure and the positions of the relaxed surface atoms obtained by the two methods are identical, with the exception of minor discrepancies which are attributed to the different relaxation procedures. The (100) surface of MoS2 contains weakly coupled S–S pairs formed by relaxation of its sulfur atoms. The results of the hydrogen adsorption show that hydrogen is adsorbed on the sulfur pairs but not on Mo atoms on the surface. Only one of the possible configurations of adsorbed H atoms on a (2×1) cell is energetically favoured, while the energy of the other configurations is higher with respect to the energy of H2 and MoS2.