Mahlberg David, Groß Axel
Institute of Theoretical Chemistry, Ulm University, 89069, Ulm, Germany.
Helmholtz Institute Ulm (HIU), Electrochemical Energy Storage, 89069, Ulm, Germany.
Chemphyschem. 2021 Jan 7;22(1):29-39. doi: 10.1002/cphc.202000838. Epub 2020 Dec 3.
Bimetallic surfaces can exhibit an improved catalytic activity through tailoring the concentration and/or the arrangement of the two metallic components. However, in order to be catalytically active, the active bimetallic surface structure has to be stable under operating conditions. Typically, structural changes in metals occur via vacancy diffusion. Based on the first-principles determination of formation energies and diffusion barriers we have performed kinetic Monte-Carlo (kMC) simulations to analyse the (meta-)stability of PtRu/Ru(0001), AgPd/Pd(111), PtAu/Au(111) and InCu/Cu(100) surface alloys. In a first step, here we consider single-atom alloys together with one vacancy per simulation cell. We will present results of the time evolution of these structures and analyse them in terms of the interaction between the constituents of the bimetallic surface.
通过调整两种金属组分的浓度和/或排列方式，双金属表面可以展现出更高的催化活性。然而，为了具有催化活性，活性双金属表面结构必须在操作条件下保持稳定。通常，金属中的结构变化是通过空位扩散发生的。基于形成能和扩散势垒的第一性原理确定，我们进行了动力学蒙特卡罗（kMC）模拟，以分析PtRu/Ru(0001)、AgPd/Pd(111)、PtAu/Au(111)和InCu/Cu(100)表面合金的（亚）稳定性。在第一步中，这里我们考虑每个模拟单元含有一个空位的单原子合金。我们将展示这些结构的时间演化结果，并根据双金属表面组分之间的相互作用对其进行分析。
