College of Physics and Information Engineering, Henan Normal University, Xinxiang, Henan, 453007, People's Republic of China.
Phys Chem Chem Phys. 2012 Dec 28;14(48):16566-72. doi: 10.1039/c2cp41441d. Epub 2012 Jul 17.
The catalytic oxidation of CO on Pt/X-graphene (X = "pri" for pristine- or "SV" for defective-graphene with a single vacancy) is investigated using the first-principles method based on density functional theory. In contrast to a Pt atom on pristine graphene, a vacancy defect in graphene strongly stabilizes a single Pt adatom and makes the Pt adatom more positively charged, which helps to weaken the CO adsorption and facilitates the O(2) adsorption, thus enhancing the activity for CO oxidation and alleviating the CO poisoning of the platinum catalysts. The CO oxidation reaction on Pt/SV-graphene has a low energy barrier (0.58 eV) by the Langmuir-Hinshelwood (LH) reaction (CO + O(2)→ OOCO → CO(2) + O(ads)) which is followed by the Eley-Rideal (ER) reaction with an energy barrier of 0.59 eV (CO + O(ads)→ CO(2)). The results validate the reactivity of catalysts on the atomic-scale and initiate a clue for fabricating carbon-based catalysts with low cost and high activity.
使用基于密度泛函理论的第一性原理方法，研究了 Pt/X-石墨烯（X = "pri"表示原始石墨烯或 "SV"表示具有单个空位的缺陷石墨烯）上 CO 的催化氧化。与原始石墨烯上的 Pt 原子相比，石墨烯中的空位缺陷强烈稳定单个 Pt 原子，并使 Pt 原子带更多正电荷，这有助于削弱 CO 的吸附并促进 O(2)的吸附，从而提高 CO 氧化的活性并减轻铂催化剂的 CO 中毒。Pt/SV-石墨烯上的 CO 氧化反应通过 Langmuir-Hinshelwood (LH)反应（CO + O(2)→ OOCO → CO(2) + O(ads)）具有低能垒（0.58 eV），随后是能垒为 0.59 eV 的 Eley-Rideal (ER)反应（CO + O(ads)→ CO(2)）。结果验证了催化剂在原子尺度上的反应活性，并为制造具有低成本和高活性的基于碳的催化剂提供了线索。
