Theoretical Studies on the Direct Propylene Epoxidation Using Gold-Based Catalysts: A Mini-Review
Theoretical Studies on the Direct Propylene Epoxidation Using Gold-Based Catalysts: A Mini-Review
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DOI：
10.3390/catal8100421
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发表时间：
2018-09
期刊：
影响因子：
3.9
通讯作者：
Jingjing Ji;Zheng Lu;Y. Lei;C. Turner
中科院分区：
文献类型：
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作者：
Jingjing Ji;Zheng Lu;Y. Lei;C. Turner
使用金基催化剂直接环氧化丙烯是一种重要的气相反应，显然是未来工业生产环氧丙烷（PO）的一条有前途的途径。例如，由少量原子组成的金纳米颗粒或团簇表现出独特的甚至意想不到的特性，因为高表面与体积原子的比例可以提供具有较低激活障碍的新反应途径。由于电荷转移，支撑材料对金纳米颗粒或团簇具有显著的影响。此外，Au（或Au基合金，如Au- pd）可以加载在支架上形成活性界面位点（或多个界面）。需要模型研究来帮助探索潜在的机制方面，并确定控制活性和选择性的关键因素。从分子和催化剂水平（例如，第一性原理计算和动力学建模）方面综述了该系统在金基催化剂上丙烯环氧化的当前理论/计算进展。这包括H2和O2吸附的分析，H2O2 （OOH）的形成，丙烯环氧化成PO，以及可能的副产物的形成。这些研究提供了对活性中心性质和主要反应机制的更好理解，因此可能用于设计具有更高效率的新型催化剂。
Direct propylene epoxidation using Au-based catalysts is an important gas-phase reaction and is clearly a promising route for the future industrial production of propylene oxide (PO). For instance, gold nanoparticles or clusters that consist of a small number of atoms demonstrate unique and even unexpected properties, since the high ratio of surface to bulk atoms can provide new reaction pathways with lower activation barriers. Support materials can have a remarkable effect on Au nanoparticles or clusters due to charge transfer. Moreover, Au (or Au-based alloy, such as Au–Pd) can be loaded on supports to form active interfacial sites (or multiple interfaces). Model studies are needed to help probe the underlying mechanistic aspects and identify key factors controlling the activity and selectivity. The current theoretical/computational progress on this system is reviewed with respect to the molecular- and catalyst-level aspects (e.g., first-principles calculations and kinetic modeling) of propylene epoxidation over Au-based catalysts. This includes an analysis of H2 and O2 adsorption, H2O2 (OOH) species formation, epoxidation of propylene into PO, as well as possible byproduct formation. These studies have provided a better understanding of the nature of the active centers and the dominant reaction mechanisms, and thus, could potentially be used to design novel catalysts with improved efficiency.