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Urea synthesis through the simultaneous electrocatalytic reduction of N2and CO2molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production, in which the development of stable, highly efficient, and highly selective catalysts to boost the chemisorption, activation, and coupling of inert N2and CO2molecules remains rather challenging. Herein, by means of density functional theory computations, we proposed a new class of two‐dimensional nanomaterials, namely, transition‐metal phosphide monolayers (TM2P, TM = Ti, Fe, Zr, Mo, and W), as the potential electrocatalysts for urea production. Our results showed that these TM2P materials exhibit outstanding stability and excellent metallic properties. Interestingly, the Mo2P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier (0.35 eV) for C–N coupling, low limiting potential (−0.39 V), and significant suppressing effects on the competing side reactions. The outstanding catalytic activity of the Mo2P monolayer can be ascribed to its optimal adsorption strength with the key *NCON species due to its moderate positive charges on the Mo active sites. Our findings not only propose a novel catalyst with high‐efficiency and high‐selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.
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Evaluation of the Catalytic Relevance of the CO‐Bound States of V‐Nitrogenase
Abstract Binding and activation of CO by nitrogenase is a topic of interest because CO is isoelectronic to N2, the physiological substrate of this enzyme. The catalytic relevance of one‐ and multi‐CO‐bound states (the lo‐CO and hi‐CO states) of V‐nitrogenase to C−C coupling and N2reduction was examined. Enzymatic and spectroscopic studies demonstrate that the multiple CO moieties in the hi‐CO state cannot be coupled as they are, suggesting that C−C coupling requires further activation and/or reduction of the bound CO entity. Moreover, these studies reveal an interesting correlation between decreased activity of N2reduction and increased population of the lo‐CO state, pointing to the catalytic relevance of the belt Fe atoms that are bridged by the single CO moiety in the lo‐CO state. Together, these results provide a useful framework for gaining insights into the nitrogenase‐catalyzed reaction via further exploration of the utility of the lo‐CO conformation of V‐nitrogenase.
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- Award ID(s):
- 1651398
- PAR ID:
- 10053976
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 13
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 3411-3414
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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