CO2 Activation on Ni/γ–Al2O3 Catalysts by First-Principles Calculations: From Ideal Surfaces to Supported Nanoparticles

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• 作者：Marius-Christian Silaghi ; Aleix Comas-Vives ; Christophe Copéret
• 刊名：ACS Catalysis
• 出版年：2016
• 出版时间：July 1, 2016
• 年：2016
• 卷：6
• 期：7
• 页码：4501-4505
• 全文大小：364K
• 年卷期：0
• ISSN：2155-5435

文摘

Due to the impact of anthropogenic CO₂ emissions on global warming, the conversion of this molecule to useful products is of increasing interest. Therefore, further understanding of the CO₂ activation is needed. Ni-based catalysts are able to dissociate and convert CO₂ into fuels, and although these systems are generally simulated using simple slab models, real catalysts are significantly more complex. They are generally composed of nanoparticles supported on oxides, being γ-Al₂O₃ one of the most widely used supports. In this study, we perform ab initio simulations in order to model the CO₂ activation on Ni nanoparticles supported on γ-Al₂O₃. Starting from ideal surface terminations, going to Ni nanoparticles (0.5–1 nm) and up to γ-Al₂O₃ supported Ni nanoparticles, the role of terraces, steps, edges, and the support is evaluated for this chemical transformation. The metal–oxide interface provides the most active sites for CO₂ activation, due to a synergistic effect between the nickel nanoparticles and the Lewis acidic sites of γ-Al₂O₃.