The overall activity of the oxygen reduction reaction (ORR) over multifaceted nanoparticles is typically interpreted as a linear combination of the ORR activity of different facets and surface site-types present on these particles. It is thus implicitly assumed that (i) edge effects are local phenomena and (ii) different facets are kinetically isolated, i.e. transfer of adsorbates over the edge is kinetically limited. Here we use rhombic nanorod models and density functional theory, with atomic O as a probe, to investigate these assumptions. The adsorption energy of atomic O was found to be virtually independent of the distance from the nanorod edge beyond the edge atomic row, indicating a localized edge effect. A kinetic connection between two adjacent facets however cannot be ruled out. The connection between the adjacent Pt{100} and Pt{111} facets, through atomic O diffusion, is kinetically more favorable at 1.0 ML edge coverage compared to 0.5 ML edge coverage as a result of repulsive lateral interactions between co-adsorbed O atoms and the corresponding flattening of the potential energy surface.

氧还原反应（ORR）在多面纳米粒子上的总体活性通常被解释为不同刻面的ORR活性与这些颗粒上存在的表面位点类型的线性组合。因此隐式地假设（i）边缘效应是局部现象，并且（ii）在动力学上隔离了不同的面，即，在动力学上限制了吸附物在边缘上的转移。在这里，我们使用菱形纳米棒模型和密度泛函理论（以原子O为探针）来研究这些假设。发现原子O的吸附能实际上与距纳米棒边缘超出边缘原子行的距离无关，这表明存在局部边缘效应。但是，不能排除两个相邻面之间的动力学联系。