Abstract Single-atom catalysts have become a hot topic in chemical industry and environmental engineering recently, which put stress on the studies of stability and catalytic activity of single-atom catalyst with nanomaterial substrate. In this study, the stability of Mn/GS and the adsorption behaviors of NO2, NO and NH3 are discussed through density functional theory calculations. We found that the order of the support effect of different Mn/GS was Mn/SV-GS > Mn/DV-GS > Mn/SW-GS > Mn/In-GS. Besides, the results of adsorption energies and bond lengths showed that the catalytic oxidation of NOx by Mn/GS was realized through activating N-O bond of NO2, while Mn/GS mainly played support effect in adsorption of NO and NH3. Moreover, electron transfer mechanisms of NO2, NO and NH3 adsorbed on Mn/GS are investigated. NO2 and NO act as the electron adopters while NH3 act as the electron donor in the adsorption system. At last, DOS and PDOS calculations were done to confirm the bond formation between N atom and Mn atom. These findings explored the catalytic activity and stability of NOx and NH3 in Mn/GS, which provided a guideline for the reaction mechanisms of NOx catalytic oxidation catalyzed by Mn/GS.

中文翻译：

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石墨烯基单原子锰催化剂对 NOx 和 NH3 的稳定性和催化活性：DFT 研究

摘要 单原子催化剂成为近年来化学工业和环境工程领域的研究热点，纳米材料基体的单原子催化剂的稳定性和催化活性研究受到重视。在本研究中，通过密度泛函理论计算讨论了 Mn/GS 的稳定性以及 NO2、NO 和 NH3 的吸附行为。我们发现不同Mn/GS的支撑作用顺序为Mn/SV-GS > Mn/DV-GS > Mn/SW-GS > Mn/In-GS。此外，吸附能和键长的结果表明，Mn/GS催化氧化NOx是通过激活NO2的NO键来实现的，而Mn/GS主要对NO和NH3的吸附起到支持作用。此外，研究了吸附在 Mn/GS 上的 NO2、NO 和 NH3 的电子转移机制。在吸附系统中，NO2 和 NO 作为电子接受者，而 NH3 作为电子供体。最后，进行了 DOS 和 PDOS 计算以确认 N 原子和 Mn 原子之间的键形成。这些发现探讨了 Mn/GS 中 NOx 和 NH3 的催化活性和稳定性，为 Mn/GS 催化 NOx 催化氧化的反应机理提供了指导。