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 Y2C4H0,1− 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.

Dinitrogen Activation by Heteronuclear Metal Carbide Cluster Anions Y1‐3CoC1,2−: An Experimental and DFT Study

“…[42,43] The findings of these studies on clusters may provide some molecular-level reaction mechanisms of N 2 activation on practical NRR catalysts. Particularly, clusters containing Y [44][45][46][47] or Co [48] and some metal carbide clusters, such as Y 2 C 4 À and Y 2 C 4 H À , [46] CoTaC 2 À , [48] V 3 C + , [49] V 3 C 4 À , [50] Ta 2 C 4 À , [51] PtC 4-6 À , [52] FeV 2 C 2 À , [53] FeTaC 2 À , [54] V 3-…”

“…The findings of these studies on clusters may provide some molecular‐level reaction mechanisms of N 2 activation on practical NRR catalysts. Particularly, clusters containing Y [44–47] or Co [48] and some metal carbide clusters, such as Y 2 C 4 − and Y 2 C 4 H − , [46] CoTaC 2 − , [48] V 3 C + , [49] V 3 C 4 − , [50] Ta 2 C 4 − , [51] PtC 4‐6 − , [52] FeV 2 C 2 − , [53] FeTaC 2 − , [54] V 3‐ x Ta x C 4 − ( x =0–3), [55] were found to have high reactivity toward N 2 . This work aims to experimentally observe the reactions between Y−Co heteronuclear metal carbide cluster anions and N 2 at room temperature, and theoretically analyze the reaction mechanisms based on density functional theory (DFT) calculations.…”

Nitrogen adsorption on Nb2C6H4+ cations: the important role of benzyne (ortho-C6H4)

“…Gas-phase clusters usually contain metal atoms coupled with inorganic ligands, such as oxygen, boron, hydrogen, carbon, sulfur, and so on. 29,[32][33][34][35] For example, we recently reported that in NbB 3 O 2 À , the B 3 O 2 ligand and the single Nb center can form a dual active site to promote N 2 activation and transformation. 29 In the NbH 2 À /CO 2 /N 2 system, the NbN 2 À anion is formed by the reaction of NbH 2 À with N 2 , and the NRN triple bond is cleaved with the formation of the C-N bond in the reaction of NbN 2 À with CO 2 .…”

Toward Designing Reactive Metal Clusters for Dinitrogen Activation: A Guideline Based on N2 Initial Adsorption

“…In this regard, the study of gas-phase reactions under isolated conditions with well-characterized chemical and molecular structures − constitutes an alternative way to probe the intrinsic structure–reactivity relationship of N 2 activation by metal clusters. With continuous efforts from many research groups, to date, a variety of homo/heteronuclear metal clusters have been successfully identified to be capable of fully cleaving the NN triple bond, − the metal centers of which include Ti 2 , Gd 2 , Ta 2 , − , Ta 3 , Ta 4 , Ta 6 , FeTa, V 3 , , FeV 2 , Sc 2 , Nb, ,, etc., as summarized in Figure . Considering the high NN bond strength, the mechanistic focus of these studies was often to elucidate the NN cleavage pathway.…”