Mechanistic details of catalytic reactions are critical to the development of improved catalysts. Here, we perform high quality Born-Oppenheimer molecular dynamics simulations of the reaction mechanisms associated with hydrogen-assisted CO2 reduction on Ni(110). The simulation results show direct theoretical evidence for both associative and redox mechanisms in the reaction of atomic hydrogen with CO2. Because H2 is dissociatively chemisorbed on Ni(110) with nearly unit probability, the mechanisms we find are also relevant to the reverse water-gas shift reaction (H2 with adsorbed CO2). Furthermore, we provide the first real-time demonstration of both Eley-Rideal (ER) and hot atom (HA) mechanisms when H impinges on adsorbed CO2, and we show that both occur even for low kinetic energies. The trade-off between ER or HA mechanisms is found to be strongly dependent on CO2 coverage. The results are compared with recent gas/surface measurements.

中文翻译：

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氢辅助 CO2 还原镍的机理

催化反应的机理细节对于改进催化剂的开发至关重要。在这里，我们对与氢辅助 CO2 还原 Ni(110) 相关的反应机制进行了高质量的 Born-Oppenheimer 分子动力学模拟。模拟结果显示了原子氢与 CO2 反应中缔合和氧化还原机制的直接理论证据。因为 H2 以几乎单位概率化学吸附在 Ni(110) 上，我们发现的机制也与反向水煤气变换反应（H2 与吸附 CO2）有关。此外，我们首次实时演示了当 H 撞击吸附的 CO2 时 Eley-Rideal (ER) 和热原子 (HA) 机制，并且我们表明即使对于低动能，这两种机制也会发生。发现 ER 或 HA 机制之间的权衡在很大程度上取决于 CO2 覆盖率。结果与最近的气体/表面测量结果进行了比较。