Lu Zhansheng, Lv Peng, Liang Yanli, Ma Dongwei, Zhang Yi, Zhang Wenjin, Yang Xinwei, Yang Zongxian
College of Physics and Materials Science, Henan Normal University, Xinxiang 453007, China.
Phys Chem Chem Phys. 2016 Aug 21;18(31):21865-70. doi: 10.1039/c6cp02221a. Epub 2016 Jul 20.
A single metal atom stabilized on two dimensional materials (such as graphene and h-BN) exhibits extraordinary activity in the oxidation of CO. The oxidation of CO by molecular O2 on a single cobalt atom embedded in a hexagonal boron nitride monolayer (h-BN) is investigated using first-principles calculations with dispersion-correction. It is found that the single Co atom prefers to reside in a boron vacancy and possesses great stability. There are three mechanisms for CO oxidation: the traditional Eley-Rideal (ER) and Langmuir-Hinshelwood (LH) mechanisms and the termolecular Eley-Rideal (TER) mechanism proposed recently. Given the relatively small reaction barriers of the rate-limiting steps for the ER, LH and TER mechanisms (0.59, 0.55 and 0.41 eV, respectively), all three mechanisms are able to occur at low temperature. The current study may provide useful clues to develop low cost single atom catalysts.
稳定在二维材料（如石墨烯和六方氮化硼）上的单个金属原子在一氧化碳氧化反应中表现出非凡的活性。利用含色散校正的第一性原理计算方法，研究了嵌入六方氮化硼单层（h-BN）中的单个钴原子上分子氧对一氧化碳的氧化反应。研究发现，单个钴原子倾向于占据硼空位并具有很高的稳定性。一氧化碳氧化存在三种反应机理：传统的埃里-里德（ER）机理、朗缪尔-欣谢尔伍德（LH）机理以及最近提出的三分子埃里-里德（TER）机理。鉴于ER、LH和TER机理中速率限制步骤的反应势垒相对较小（分别为0.59、0.55和0.41电子伏特），这三种机理在低温下均有可能发生。本研究可为开发低成本单原子催化剂提供有用线索。
