Department of Materials Science and Engineering, KAIST, 291-Daehak-ro, Yuseong-gu, Daejeon, 34141 Korea.
Nanoscale. 2017 Apr 20;9(16):5244-5253. doi: 10.1039/c7nr01382e.
We use density functional theory calculations of Pt@Cu core@shell nanoparticles (NPs) to design bifunctional poison-free CO oxidation catalysts. By calculating the adsorption chemistry under CO oxidation conditions, we find that the Pt@Cu NPs will be active for CO oxidation with resistance to CO-poisoning. The CO oxidation pathway at the Pt-Cu interface is determined on the Pt NP covered with a full- and partial-shell of Cu. The exposed portion of the Pt core preferentially binds CO and the Cu shell binds O, supplying oxygen for the reaction. The Pt-Cu interface provides CO-oxidation sites that are not poisoned by either CO or O. Additional computational screening shows that this separation of reactant binding sites is possible for several other core@shell NPs. Our results indicate that the metal-metal interface within a single NP can be optimized for design of bifunctional catalytic systems with improved performance.
我们使用 Pt@Cu 核壳纳米粒子（NPs）的密度泛函理论计算来设计无毒性双功能 CO 氧化催化剂。通过计算 CO 氧化条件下的吸附化学，我们发现 Pt@Cu NPs 将具有 CO 氧化活性，并且对 CO 中毒具有抗性。在 Pt 覆盖有完整和部分壳层的 Cu 的 NPs 上确定了 Pt-Cu 界面处的 CO 氧化途径。Pt 核的暴露部分优先结合 CO，而 Cu 壳结合 O，为反应提供氧。Pt-Cu 界面提供了不会被 CO 或 O 中毒的 CO 氧化位点。额外的计算筛选表明，对于其他几种核壳 NPs，也可以实现这种反应物结合位点的分离。我们的结果表明，单个 NP 内的金属-金属界面可以针对设计具有改进性能的双功能催化体系进行优化。
