scholarly journals High-Throughput Screening Single-Atom Alloy for Electroreduction of Dinitrogen to Ammonia

Author(s):  
Guokui Zheng ◽  
Ziqi Tian ◽  
Xingwang Zhang ◽  
Liang Chen ◽  
Xu Qian ◽  
...  

<p></p><p>Exploring electrocatalyst with high activity, selectivity and stability is essential for development of applicable electrocatalytic ammonia synthesis technology. By performing density functional theory calculations, we systematically investigated a series of transition-metal doped Au-based single atom alloys (SAAs) as promising electrocatalysts for nitrogen reduction reaction (NRR). For Au-based electrocatalyst, the first hydrogenation step (*N<sub>2</sub>→*NNH) normally determines the limiting potential of the overall reaction process. Compared with pristine Au(111) surface, introducing single atom can significantly enhance the binding strength of N<sub>2</sub>, leading to decreased energy barrier of the key step, i.e., ΔG(*N<sub>2</sub>→*NNH). According to simulation results, three descriptors were proposed to describe ΔG(*N<sub>2</sub>→*NNH), including ΔG(*NNH), <i>d</i>-band center, and . Eight doped elements (Ti, V, Nb, Ru, Ta, Os, W, and Mo) were initially screened out with limiting potential ranging from -0.75V to -0.30 V. Particularly, Mo- and W-doped systems possess the best activity with limiting potentials of -0.30 V, respectively. Then the intrinsic relationship between structure and the potential performance was further analyzed by using machine-learning. The selectivity, feasibility, stability of these candidates were also evaluated, confirming that SAA containing Mo, Ru ,Ta, and W could be outstanding NRR electrocatalysts. This work not only broadens the understating of SAA application in electrocatalysis, but also devotes to the discovery of novel NRR electrocatalysts.</p><br><p></p>

2021 ◽  
Author(s):  
Guokui Zheng ◽  
Ziqi Tian ◽  
Xingwang Zhang ◽  
Liang Chen ◽  
Xu Qian ◽  
...  

<p></p><p>Exploring electrocatalyst with high activity, selectivity and stability is essential for development of applicable electrocatalytic ammonia synthesis technology. By performing density functional theory calculations, we systematically investigated a series of transition-metal doped Au-based single atom alloys (SAAs) as promising electrocatalysts for nitrogen reduction reaction (NRR). For Au-based electrocatalyst, the first hydrogenation step (*N<sub>2</sub>→*NNH) normally determines the limiting potential of the overall reaction process. Compared with pristine Au(111) surface, introducing single atom can significantly enhance the binding strength of N<sub>2</sub>, leading to decreased energy barrier of the key step, i.e., ΔG(*N<sub>2</sub>→*NNH). According to simulation results, three descriptors were proposed to describe ΔG(*N<sub>2</sub>→*NNH), including ΔG(*NNH), <i>d</i>-band center, and . Eight doped elements (Ti, V, Nb, Ru, Ta, Os, W, and Mo) were initially screened out with limiting potential ranging from -0.75V to -0.30 V. Particularly, Mo- and W-doped systems possess the best activity with limiting potentials of -0.30 V, respectively. Then the intrinsic relationship between structure and the potential performance was further analyzed by using machine-learning. The selectivity, feasibility, stability of these candidates were also evaluated, confirming that SAA containing Mo, Ru ,Ta, and W could be outstanding NRR electrocatalysts. This work not only broadens the understating of SAA application in electrocatalysis, but also devotes to the discovery of novel NRR electrocatalysts.</p><br><p></p>


Author(s):  
Zhen Feng ◽  
Zelin Yang ◽  
Xiaowen Meng ◽  
Fachuang Li ◽  
Zhanyong Guo ◽  
...  

The development of single-atom catalysts (SACs) for electrocatalytic nitrogen reduction reaction (NRR) remains a great challenge. Using density functional theory calculations, we design a new family of two-dimensional metal-organic frameworks...


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhen-Yu Wu ◽  
Mohammadreza Karamad ◽  
Xue Yong ◽  
Qizheng Huang ◽  
David A. Cullen ◽  
...  

AbstractElectrochemically converting nitrate, a widespread water pollutant, back to valuable ammonia is a green and delocalized route for ammonia synthesis, and can be an appealing and supplementary alternative to the Haber-Bosch process. However, as there are other nitrate reduction pathways present, selectively guiding the reaction pathway towards ammonia is currently challenged by the lack of efficient catalysts. Here we report a selective and active nitrate reduction to ammonia on Fe single atom catalyst, with a maximal ammonia Faradaic efficiency of ~ 75% and a yield rate of up to ~ 20,000 μg h−1 mgcat.−1 (0.46 mmol h−1 cm−2). Our Fe single atom catalyst can effectively prevent the N-N coupling step required for N2 due to the lack of neighboring metal sites, promoting ammonia product selectivity. Density functional theory calculations reveal the reaction mechanisms and the potential limiting steps for nitrate reduction on atomically dispersed Fe sites.


Author(s):  
Tianchun Li ◽  
Manman Li ◽  
Xinyue Zhu ◽  
Juan Zhang ◽  
Yu Jing

Two dimensional (2D) conjugated metal organic frameworks (MOFs) which feature single atom catalysts are promising electrocatalysts to promote oxygen reduction reaction (ORR). Here, by means of density functional theory calculations...


2020 ◽  
Vol 8 (39) ◽  
pp. 20402-20407
Author(s):  
Yujin Ji ◽  
Yifan Li ◽  
Huilong Dong ◽  
Lifeng Ding ◽  
Youyong Li

Grand canonical density functional theory calculations reveal that the Ru–N4 motif is the superior catalytic site for eNRR rather than the Ru–N3 motif.


2020 ◽  
Author(s):  
Wu Tong ◽  
Bolong Huang ◽  
Pengtang Wang ◽  
Qi Shao ◽  
Xiaoqing Huang

Abstract Understanding the correlation between exposed surfaces and performances of controlled nanocatalysts can aid effective strategies to enhance electrocatalysis, but this is as yet unexplored for the nitrogen reduction reaction (NRR). Here, we first report controlled synthesis of well-defined Pt3Fe nanocrystals with tunable morphologies (nanocube, nanorod and nanowire) as ideal model electrocatalysts for investigating the NRR on different exposed facets. The detailed electrocatalytic studies reveal that the Pt3Fe nanocrystals exhibit shape-dependent NRR electrocatalysis. The optimized Pt3Fe nanowires bounded with high-index facets exhibit excellent selectivity (no N2H4 is detected), high activity with NH3 yield of 18.3 μg h−1 mg−1cat (0.52 μg h−1 cm−2ECSA; ECSA: electrochemical active surface area) and Faraday efficiency of 7.3% at −0.05 V versus reversible hydrogen electrode, outperforming the {200} facet-enclosed Pt3Fe nanocubes and {111} facet-enclosed Pt3Fe nanorods. They also show good stability with negligible activity change after five cycles. Density functional theory calculations reveal that, with high-indexed facet engineering, the Fe-3d band is an efficient d-d coupling correlation center for boosting the Pt 5d-electronic exchange and transfer activities towards the NRR.


2021 ◽  
Author(s):  
Fernanda Juarez ◽  
Hui Yin ◽  
Axel Gross

The surface structures of promising cathode materials for zinc-air batteries, Mn3O4 and Co3O4, have been systematically studied under operating conditions by density functional theory calculations. The environment has been taken into account using grand-canonical schemes both for gas-phase and electrochemical conditions. By analysing the structures appearing in the calculated phase diagrams and Pourbaix diagrams in detail, we derive the factors underlying their stability in the gas phase and under electrochemical conditions. Changes in charge, oxidation states and spin states of the metal cations on the surface are discussed and their feasibility as active centers for the oxygen evolution and reduction reaction is thoroughly analyzed.


2010 ◽  
Vol 55 (27) ◽  
pp. 7975-7981 ◽  
Author(s):  
Vladimir Tripković ◽  
Egill Skúlason ◽  
Samira Siahrostami ◽  
Jens K. Nørskov ◽  
Jan Rossmeisl

Author(s):  
Xin-Chen Zhu ◽  
Wei Zhang ◽  
Qian Xia ◽  
Anfu Hu ◽  
Jian Jiang ◽  
...  

To study the effect of coordination field on catalytic property is critical for rational design of outstanding electrocatalyst for H2O2 synthesis. Herein, via density functional theory calculations, we built an...


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