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Experimental and Theoretical Study of N₂ Adsorption on Hydrogenated Y₂C₄H^- and Dehydrogenated Y₂C₄^- Cluster Anions at Room Temperature.

ABSTRACT: The adsorption of atmospheric dinitrogen (N₂) 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 N₂, while the role of hydrogen has not been comprehensively studied. Herein, we report the N₂ adsorption on the well-defined Y₂C₄H_0,1^- cluster anions under mild conditions by using mass spectrometry and density functional theory calculations. The mass spectrometry results reveal that the reactivity of N₂ adsorption on Y₂C₄H^- is 50 times higher than that on Y₂C₄^- clusters. Further analysis reveals the important role of the H atom: (1) the presence of the H atom modifies the charge distribution of the Y₂C₄H^- anion; (2) the approach of N₂ to Y₂C₄H^- is more favorable kinetically compared to that to Y₂C₄^-; and (3) a natural charge analysis shows that two Y atoms and one Y atom are the major electron donors in the Y₂C₄^- and Y₂C₄H^- 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 N₂.

SUBMITTER: Gao M

PROVIDER: S-EPMC9266966 | biostudies-literature |

REPOSITORIES: biostudies-literature

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