密度函数理论研究了 γ-Al2O3 - 波希米特转化如何影响水相反应期间的碳演变
Tinnakorn Saelee1, Phakaorn Apichoksiri1, Meena Rittiruam2
1High-Performance Computing Unit (CECC-HCU), Center of Excellence on Catalysis and Catalytic Reaction Engineering (CECC), Chulalongkorn University, Bangkok, 10330, Thailand; Center of Excellence on Catalysis and Catalytic Reaction Engineering (CECC), Chulalongkorn University, Bangkok, 10330, Thailand; Saelee Group, Chulalongkorn University, Bangkok, 10330, Thailand.
Chemosphere
|August 19, 2023
概括
这项研究揭示了焦炭如何在玛 (γ-Al2O3) 催化剂表面形成. 水氧化促进了焦炭的演化,循环结构在热力学上比异形结构更受青,以获得更高的焦炭形成.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 催化剂是一种催化剂.
背景情况:
- 玛 (γ-Al2O3) 广泛用于催化,但受到快速失活的影响.
- 焦炭形成是γ-Al2O3催化剂中脱活的主要原因.
- 了解焦炭形成机制对于改善催化剂寿命至关重要.
研究的目的:
- 阐明焦炭在γ-Al2O3的表面上形成和演变的机制.
- 调查表面化在焦炭沉积和生长中的作用.
- 为了确定较高的焦炭物种的首选结构.
主要方法:
- 计算的表面科学方法.
- 在不同表面条件下 (清洁,部分化,完全化) 模拟焦炭沉积和演变.
- 对焦炭结构的热力学偏好的分析.
主要成果:
- γ-Al2O3(110) 表面促进了最初的原子焦炭沉积和二元化.
- 表面的基 (OH) 物种促进焦炭向更高的寡合体 (Cn,n ≥3) 的演变.
- 循环焦炭结构在热力学上比形结构更受青,用于更高的焦炭形成.
结论:
- 表面化在g-Al2O3.3上的焦炭形成的进展中起着至关重要的作用.
- γ-Al2O3表面的电子捐赠性影响焦炭沉积.
- 对焦炭形成机制的洞察力可以指导开发更稳定的γ-Al2O3催化剂.
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