Bulk structures of PtO and PtO 2 from density functional calculations
Bulk structures of PtO and PtO 2 from density functional calculations
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DOI：
10.1103/physrevb.84.100101
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发表时间：
2011-09
影响因子：
3.7
通讯作者：
R. K. Nomiyama;M. Piotrowski;J. D. Silva
中科院分区：
文献类型：
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作者：
R. K. Nomiyama;M. Piotrowski;J. D. Silva
铂在催化和电化学中起着重要的作用，已知氧与铂表面的直接相互作用可导致铂氧化物（PtO${}_{x}$）的形成，从而影响反应活性。为了促进对PtO${}_{x}$原子结构的原子论理解，我们报告了一项体PtO${}_{x}$原子结构的密度泛函理论研究（$1\ensuremath{\le}x\ensuremath{\le}2$）。从我们的计算中，我们确定了PtO的最低能量结构（GeS型，空间群$Pnma$），其能量比W. J. Moore和L. Pauling提出的结构低0.181 eV。点。化学。Soc. 63,1392 (1941)] （PtS类型）。此外，PtO${}_{2}$确定了两个原子结构，它们在能量上几乎是简并的，其中PtO${}_{2}$是目前报道的能量最低的原子结构（CaCl${}_{2}$型）。根据我们的结果和分析，我们认为即使在较低的O组成下，Pt和O原子也倾向于通过形成Pt-Pt键形成PtO${}_{x}$中的八面体基序。
Platinum plays an important role in catalysis and electrochemistry, and it is known that the direct interaction of oxygen with Pt surfaces can lead to the formation of platinum oxides (PtO${}_{x}$), which can affect the reactivity. To contribute to the atomistic understanding of the atomic structure of PtO${}_{x}$, we report a density functional theory study of the atomic structure of bulk PtO${}_{x}$ ($1\ensuremath{\le}x\ensuremath{\le}2$). From our calculations, we identified a lowest-energy structure (GeS type, space group $Pnma$) for PtO, which is 0.181 eV lower in energy than the structure suggested by W. J. Moore and L. Pauling [J. Am. Chem. Soc. 63, 1392 (1941)] (PtS type). Furthermore, two atomic structures were identified for PtO${}_{2}$, which are almost degenerate in energy with the lowest-energy structure reported so far for PtO${}_{2}$ (CaCl${}_{2}$ type). Based on our results and analysis, we suggest that Pt and O atoms tend to form octahedron motifs in PtO${}_{x}$ even at lower O composition by the formation of Pt-Pt bonds.