在过渡金属和双金属表面上,氧化的线性缩放关系
Dipika Rajendra Kanchan1, Arghya Banerjee1
1Department of Chemical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab, 140001, India.
布伦斯特德-埃文斯-波兰尼 (BEP) 和过渡状态缩放 (TSS) 关系指导水解氧化 (HDO) 催化剂设计. 这项研究开发了这些关系,用于各种金属表面上的激活,有助于加速催化剂的发现.
科学领域:
- 计算化学和材料科学计算化学和材料科学
- 催化和表面科学研究
- 可再生能源和生物质转化转化.
背景情况:
- 氧化 (HDO) 对于将生物油升级为有价值的燃料和化学品至关重要.
- 对HDO的合理催化剂设计需要了解基本反应步骤和缩放关系.
- 布伦斯特德-埃文斯-波兰尼 (BEP) 和过渡状态缩放 (TSS) 关系为催化剂性能提供了预测能力.
研究的目的:
- 在HDO期间激活的基本步骤中开发BEP和TSS关系.
- 研究各种单金属 (Ni,Co,Rh,Ru,Pt,Pd,Fe,Ir) 和双金属 (PtFe) 催化剂的活性.
- 为加速发现高效HDO催化剂提供计算框架.
主要方法:
- 用密度函数理论 (DFT) 的计算来研究 furan 激活通路.
- 系统地开发了BEP和TSS关系,用于C和O化和CHx-OHy裂变.
- 对单金属和双金属 (PtFe) 表面进行选,以检测氧化活性.
主要成果:
- 环开口屏障对金属表面的碳和氧结合强度很敏感.
- 特定的金属表面有利于不同的HDO通路:Ir,Pt,Pd,Rh有利于氧化物,而Fe,Ni有利于脱氧产品.
- PtFe双金属催化剂通过降低环开放和脱氧障碍,显示出增强的HDO活性.
结论:
- 开发的BEP和TSS关系适用于单金属表面,部分适用于用于环开/化的双金属表面.
- BEP/TSS关系的预测能力对于双金属表面的开环激活是有限的,因为过渡状态的结合改变了.
- 建立的关系可以为HDO过程中有效的催化剂发现提供微动力学模型的信息.
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