在Fe-功能化Au上激发状态N2解离路径
John Mark P Martirez1, Emily A Carter1
1Department of Mechanical and Aerospace Engineering and ‡School of Engineering and Applied Science, Princeton University , Princeton, New Jersey 08544-5263, United States.
Journal of the American Chemical Society
|March 8, 2017
概括
局部表面等离子共振 (LSPRs) 可以实现光激活催化. 这项研究表明,LSPR可以显著降低分离的能量障碍,这是氨合成的关键步骤.
科学领域:
- 表面科学和催化
- 塑和纳米技术
- 计算化学
背景情况:
- 局部表面等离子共振 (LSPR) 促进金属纳米粒子的光驱动化学反应.
- (N2) 分离是通过哈伯-博什过程合成氨的具有挑战性的,耗能的步骤.
- 克服N2解离的高激活能量对于高效的氨生产至关重要.
研究的目的:
- 研究LSPRs在催化表面降低N2解离的激活能量的潜力.
- 通过等离子效应探索使用化Au111) 表面进行增强的N2解离.
- 在Fe-doped Au111表面上计算N2解离的激发状态潜在能量表面.
主要方法:
- 密度函数嵌入理论与嵌入的n电子价值二次扰动理论.
- 对N2解离的兴奋状态潜在能量表面的计算.
- 在Fe-doped Au111) 表面上模拟N2解离.
主要成果:
- 在Fe-doped Au111上,N2的基态解离激活能量被计算为4.74 eV/N2,Fe是活性位点.
- 在电子激发状态之间确定了多重共振能量转移 (RET).
- 这些RET有效地降低了解离障碍到1.33 eV.
结论:
- 与共振能量转移相结合的LSPR可以显著降低N2解离的激活屏障.
- 这种用等离子增强的方法为克服氨合成的动力限制提供了有希望的途径.
- 这些发现表明了利用光能促进具有挑战性的化学转换的策略.
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