通过Ru/C12A7电子催化剂合成反应的性质
James Kammert1, Jisue Moon1,2, Yongqiang Cheng3
1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Journal of the American Chemical Society
|April 7, 2020
概括
表面吸附的,而不是封闭的化物,是通过电化催化剂合成氨的关键. 电化支持增强反应性中间覆盖,提高氨生产效率.
科学领域:
- 催化科学
- 材料科学
- 表面化学
背景情况:
- 对在温和条件下合成氨的催化剂重新感兴趣.
- 基于电子的催化剂,特别是氧化 (Ru/C12A7) 上的,对N2激活具有前景.
- 在Ru/C12A7催化中,电极支和反应性物种的确切作用尚不清楚.
研究的目的:
- 阐明物种和电极支持在Ru/C12A7上的氨合成中的作用.
- 提供关于活性和电极功能的直接证据.
主要方法:
- 在现场中子散射技术 (中子衍射,无弹性中子光谱).
- 密度函数理论 (DFT) 的计算.
- 温度编程反应和稳定状态同位素瞬态动力分析 (SSITKA).
主要成果:
- 表面吸附的,而不是封闭的化物,被确定为氨合成的主要反应物种.
- 在C12A7中封闭的化物种是热和化学稳定的.
- 与氧化物形式 (15%) 相比,电极支持显著提高了Ru的反应中间覆盖率,减轻了H2中毒.
结论:
- 在Ru/C12A7电子催化剂上,表面的物种对氨合成至关重要.
- 通过增加中间覆盖和防止催化剂中毒,C12A7的电极体形式在促进催化中发挥着至关重要的作用.
- 这些发现有助于对基于电极的氨基合成和化反应的理解.
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