Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China.
Int J Mol Sci. 2022 Jun 23;23(13):6976. doi: 10.3390/ijms23136976.
The adsorption of atmospheric dinitrogen (N) on transition metal sites is an important topic in chemistry, which is regarded as the prerequisite for the activation of robust N≡N bonds in biological and industrial fields. Metal hydride bonds play an important part in the adsorption of N, while the role of hydrogen has not been comprehensively studied. Herein, we report the N adsorption on the well-defined YCH cluster anions under mild conditions by using mass spectrometry and density functional theory calculations. The mass spectrometry results reveal that the reactivity of N adsorption on YCH is 50 times higher than that on YC clusters. Further analysis reveals the important role of the H atom: (1) the presence of the H atom modifies the charge distribution of the YCH anion; (2) the approach of N to YCH is more favorable kinetically compared to that to YC; and (3) a natural charge analysis shows that two Y atoms and one Y atom are the major electron donors in the YC and YCH anion clusters, respectively. This work provides new clues to the rational design of TM-based catalysts by efficiently doping hydrogen atoms to modulate the reactivity towards N.
大气中氮气（N）在过渡金属位点上的吸附是化学中的一个重要课题，被认为是生物和工业领域中强 N≡N 键活化的前提条件。金属氢化物键在 N 的吸附中起着重要作用，而氢的作用尚未得到全面研究。在此，我们通过质谱和密度泛函理论计算报告了在温和条件下，在经过良好定义的 YCH 团簇阴离子上的 N 吸附。质谱结果表明，N 在 YCH 上的吸附反应活性比在 YC 团簇上高 50 倍。进一步的分析揭示了 H 原子的重要作用：（1）H 原子的存在改变了 YCH 阴离子的电荷分布；（2）与 YC 相比，N 接近 YCH 的动力学更有利；（3）自然电荷分析表明，在 YC 和 YCH 阴离子团簇中，两个 Y 原子和一个 Y 原子分别是主要的电子供体。这项工作通过高效掺杂氢原子来调节对 N 的反应性，为基于 TM 的催化剂的合理设计提供了新的线索。
