First-Principles Study on Stability and Electronic Structures of Pt-Rh Bimetallic Nanoparticles
First-Principles Study on Stability and Electronic Structures of Pt-Rh Bimetallic Nanoparticles
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DOI：
10.2320/matertrans.m2009295
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发表时间：
2010-02
影响因子：
1.2
通讯作者：
Koretaka Yuge;T. Ichikawa;J. Kawai
中科院分区：
文献类型：
--
作者：
Koretaka Yuge;T. Ichikawa;J. Kawai
用第一性原理计算方法研究了Pt-Rh纳米颗粒中Pt原子的能量稳定性和电子结构。Pt原子在能量上更倾向于表面位置（顶点、边缘和（100））而不是亚表面和核心位置，这归因于与Rh相比Pt表面能较低。纳米粒子的顶点是铂原子最有利的位置，具有最低的配位数。由费米能级测量的Pt原子d态电子贡献的能带中心与Pt的配位数呈负相关。这可以归因于Pt d带的态密度二阶矩与配位数的正相关性。Pt偏析的表面，预计主要是由于贡献Pt的现场偏析能量相比，弱有序化倾向的Pt-Rh不喜欢的原子对。[doi：10.2320/matertrans.M2009295]
Energetic stability and electronic structures of Pt atoms in Pt-Rh nanoparticle is investigated by first-principles calculation. Pt atom energetically prefer surface sites (vertex, edge, and (100)) rather than subsurface and core site, which is attributed to lower Pt surface energy compared with Rh. Vertex of nanoparticle is the most favorable site for Pt atom, which has lowest coordination numbers. Band center of d-state electronic contribution for Pt atom measured from the Fermi energy exhibit negative dependence with respect to Pt coordination number. This can be attributed to positive dependence of second-order moment of density of states for the Pt d-band on the coordination number. Pt segregation to the surface is expected due mainly to contribution from Pt on-site segregation energy compared with weak ordering tendency of Pt-Rh unlike-atom pairs. [doi:10.2320/matertrans.M2009295]