High spin polarized Fe₂ cluster combined with vicinal nonmetallic sites for catalytic ammonia synthesis from a theoretical perspective

Abstract

Compared to other Fen (n > 2) clusters, Fe2 cluster catalysts combined with vicinal nonmetallic sites are expected to be an ideal catalyst for ammonia synthesis with a lower N–H formation (0.47 eV) and N–N dissociation (0.50 eV) energy barrier at the same time.

Strategies for avoiding the scaling relationship in ammonia synthesis with non-thermal plasma methods – the “shift” or “break” approach

“…Many active species can be produced in the gas phase and on the surface between the atoms and excited species. Besides, the decomposition of NH 3 as a side reaction may occur via eqn (31) and (32)…”

“…The scaling relationship between adsorption energy and activation energy species on the catalyst surface can be shifted by lowering the N 2 activation energy barrier with the active hydrogen species from H 2 dissociation. Zhu et al 32 constructed a B-doped mesoporous graphite carbon nitride-supported Fe 2 catalyst (Fe 2 /B/mpg-C 3 N 4 ). It was easy to hydrogenate *N 2 to form *NHNH 2 species by the Fe 2 catalyst, leading to a low N dissociation energy barrier (0.50 eV).…”

Computational design of catalysts for ammonia synthesis

“…This has significant impact on the reaction mechanism of ammonia synthesis. Similar to on extended metal surfaces, ammonia synthesis on nanoparticles is considered to follow the traditional dissociative mechanism [50]. When catalysts size is reduced to the cluster or single-atom region, ammonia synthesis may proceed through the associative mechanism which is common in biological nitrogen fixation and eNRR.…”

“…When catalysts size is reduced to the cluster or single-atom region, ammonia synthesis may proceed through the associative mechanism which is common in biological nitrogen fixation and eNRR. In the associative mechanism, N 2 will associate with H atoms to form N 2 H x species first before the cleavage of the N-N bond, strength of which is weakened by the accumulated H atoms [50]. Peng and co-workers compared N 2 dissociation barriers on g-C 3 N 4 supported Fe x (x = 2, 3, and 4) clusters with that on Fe (211) and found decreasing barriers from 2.75 to 0.50 eV with increasing coordination number of Fe (Fig.…”

Quantitative analysis of molecular surface: systematic application in the sodiation mechanism of a benzoquinone-based pillared compound as a cathode

“…In recent academic studies, Huan et al explored the lithiation process of the P5Q cathode based on density functional theory (DFT) for the first time. [25][26][27][28][29] All lithiated structures of P5Q were compared, and the lowest energy one was selected to predict the possible Li-binding site. However, it is time-consuming and some possible product structures could be neglected easily.…”