通过Kinetic Monte Carlo对单原子合金纳米粒子进行选择性乙化
Mikkel Jørgensen1, Henrik Grönbeck1
1Department of Physics and Competence Centre for Catalysis , Chalmers University of Technology , 412 96 Göteborg , Sweden.
Journal of the American Chemical Society
|May 8, 2019
概括
单原子合金,特别是嵌入在铜中的,显著提高了乙烯化催化剂的选择性. 纳米粒子设计应优先考虑 (111) 边缘部位,以获得最佳的乙烯生产.
科学领域:
- 材料科学
- 催化剂
- 表面化学
背景情况:
- 单原子合金通过隔离宿主金属中的金属位点来提高催化剂的选择性.
- 纳米粒子催化剂对于工业应用至关重要,因为它们的表面积很大.
研究的目的:
- 使用铜 (Pd/Cu) 纳米粒子对乙烯进行选择性化.
- 为了比较Pd/Cu纳米颗粒与扩展的Pd(111) 和Pd/Cu(111) 表面的催化性能.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 使用动力蒙特卡洛 (kMC) 模拟来建模反应机制.
主要成果:
- 将 (Pd) 嵌入铜 (Cu) 系统可以显著提高选择性.
- 纳米颗粒上的反应机制与延伸表面的反应机制有根本的不同.
- 发现纳米粒子边缘和角位降低了选择性.
结论:
- 在乙烯化中,Pd/Cu单原子合金具有较高的选择性.
- 选择性乙化催化剂的设计应最大限度地提高Pd/Cu纳米颗粒上的边缘位点 (111).
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