Selective Oxidation of Hydrogen in the Presence of Propylene over Pt-Based Core鈥揝hell Nanocatalysts

详细信息    查看全文

• 作者：Ming-Lei Yang ; Chen Fan ; Yi-An Zhu ; Zhi-Jun Sui ; Xing-Gui Zhou ; De Chen
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：September 17, 2015
• 年：2015
• 卷：119
• 期：37
• 页码：21386-21394
• 全文大小：531K
• ISSN：1932-7455

文摘

Coupling of propane dehydrogenation with selective hydrogen oxidation is a practical strategy to achieve high propylene yield and low energy consumption. In this work, the detailed reaction mechanism on Pt(111) is explored using density functional theory calculations and microkinetic modeling to benefit the design of new catalysts. Calculated results indicate that the O₂ dissociation pathway is dominant for hydrogen oxidation, and the dissociation of O₂ is kinetically relevant. With the comparison between the energy barriers for dehydrogenation and oxidation, propyne is found to be the starting point for C3 oxidation. To obtain a high hydrogen oxidation rate and suppress the consumption of propylene, the catalytic performance of 11 M@Pt (M = Fe, Co, Ni, Cu, Ru, Rh, Os, Ir, Pd, Ag, and Au) core鈥搒hell surfaces is examined. Among all the core鈥搒hells, Ag@Pt not only has a high catalytic activity for hydrogen oxidation, but also exhibits a high selectivity toward propylene and is, therefore, the best candidate for selective hydrogen oxidation in the presence of propylene.