Catalytic Dissociation of Water on the (001), (011), and (111) Surfaces of Violarite, FeNi 2 S 4 : A DFT-D2 Study
Catalytic Dissociation of Water on the (001), (011), and (111) Surfaces of Violarite, FeNi 2 S 4 : A DFT-D2 Study
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紫罗兰石 FeNi 2 S 4 的 (001)、(011) 和 (111) 表面上水的催化离解：DFT-D2 研究
DOI：
10.1021/jp409522q
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Haider S
中科院分区：
文献类型：
--
作者：
Haider S
铁镍硫化物矿物紫铅矿与生命起源理论相关，具有潜在的催化活性。在这里，我们提出了密度泛函理论的模拟，修正了体相和表面的长程相互作用(DFT-D2)，以及随后的水的吸附和解离。低密勒指数面的弛豫表明，(001)面在能量上是最有利的，而(111)面是最不稳定的，但对水的反应性也是最小的。对反应能路径的计算表明，水最有可能在(011)面上发生吸附，因为这稳定了低配位的原子。Fe的八面体中心比四面体的Ni中心具有更强的吸附能，表面吸附的水分子的解离促进了后续分子的吸附。水的离解也最有可能发生在(011)表面，这反映在计算的总反应能的负值上。结果表明，缔合吸附优先于解离吸附。
The iron–nickel sulfide mineral violarite is relevant in origin of life theories and has potential catalytic activity. Here we present density functional theory simulations with a correction for the long-range interactions (DFT-D2) of the bulk and surfaces of violarite, and subsequent adsorption and dissociation of water. Relaxation of the low-Miller index surfaces shows the (001) surface to be energetically the most favorable, while the (111) is the least stable surface, but also the least reactive with respect to water. Calculation of the reaction energy pathways reveals that water adsorption is most likely to occur on the (011), as this stabilizes the low-coordinated atoms. Stronger adsorption energies are found for Fe octahedral sites, over tetrahedral Ni sites, with the dissociation of an adsorbed water molecule on the surface facilitating the adsorption of a subsequent molecule. Dissociation of water is also most likely to occur on the (011) surface, as reflected by negative values calculated for the overall reaction energies. The results ultimately show that associative adsorption of water is preferred over dissociative adsorption.