在,铁,,,和表面上吸附剂诱导的亚原子形成
1Department of Chemical & Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
JACS Au
|September 1, 2023
概括
吸附剂可以在催化表面破坏金属对金属的键,形成原子. 这项研究表明,在和铁催化剂上,原子形成更容易,这对于像氨合成这样的反应至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 计算化学的计算化学
背景情况:
- 在催化表面上金属金属键断裂是实验和理论观察.
- 这种现象即使在温和的反应条件下也会发生.
- 了解吸附剂诱导的影响是催化剂设计的关键.
研究的目的:
- 构建密度函数理论 (DFT) 数据库用于吸附剂诱导的原子形成能量.
- 为了研究各种金属表面 (Co,Ru,Re,Li,Fe) 上的 adatom 形成.
- 为了确定条件和吸附剂,以促进金属金属结合的断裂.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 建立 adatom 形成能量的数据库.
- 对六角密封和体中心立方金属的紧密封装面和步骤边缘的分析.
- 包含Co和Ru的元稳定面部中心立体结构.
- 对18种不同的催化吸附剂的研究.
主要成果:
- 与Co,Ru和Re相比,在Li和Fe上,亚原子的形成明显更容易.
- 在室温下,氨 (NH3) 和一氧化碳 (CO) 诱导Fe(110) 上的原子形成.
- 在500-700 K的其他系统中,为阿达托姆形成确定了有利的吸附剂效应.
- 金属表面上的特定吸附剂促进了金属对金属的断裂.
结论:
- 这些发现为反应驱动的金属集群形成提供了洞察力.
- 通过 adatom 创建形成的金属集群可以作为催化剂中的活性位点.
- 这项研究与基于Li,Fe,Co,Ru和Re的催化剂有关.
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