Adsorption mechanisms and electronic and magnetic properties of oxygen on iron tetranitride

2020 ◽  
Vol 34 (19) ◽  
pp. 2050173 ◽  
Author(s):  
Zhi Li ◽  
Tong-Tong Shi ◽  
Zhen Zhao
Keyword(s):  
First Principles ◽  
Electrode Materials ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Iron Nitrides ◽  
Adsorption Mechanisms ◽  
Kinetic Activity ◽  
Average Spin ◽  
Adsorption And Dissociation ◽  
Center Site

The oxide layer on iron nitrides restricts the conductivity of electrode materials. The adsorption and dissociation processes of O2 on the Fe4N have been analyzed by using first-principles. Comparing all the O2Fe4N isomers, we find that O atom prefers to locate at the center site of Fe–Fe–Fe plane which stays away from N atom. It means that O2 molecule is dissociated on the surface of Fe4N molecule. Endothermic and exothermic processes occur with the adsorption and decomposition of O2 on the surface of Fe4N. All the O2Fe4N clusters still present higher kinetic activity. For the O2Fe4N clusters, the internal electrons transfer from 4[Formula: see text] to 3[Formula: see text] and 4[Formula: see text] orbitals which are obviously more than those transfer to the other atoms. O atoms acquire less electron from nearby Fe atoms which confirms that the adsorption of O2 on Fe4N is a physical adsorption process. The average spin of the ground-state O2Fe4N clusters is 1.805 [Formula: see text]/atom.

scholarly journals First-Principles Study on the Adsorption and Dissociation of Impurities on Copper Current Collector in Electrolyte for Lithium-Ion Batteries

Materials ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1256 ◽  
Author(s):  
Jian Chen ◽  
Chao Li ◽  
Jian Zhang ◽  
Cong Li ◽  
Jianlin Chen ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
First Principles ◽  
Density Functional ◽  
Physical Adsorption ◽  
Lithium Ion ◽  
Current Collector ◽  
Residual Water ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Adsorption And Dissociation

The copper current collector is an important component for lithium-ion batteries and its stability in electrolyte impacts their performance. The decomposition of LiPF6 in the electrolyte of lithium-ion batteries produces the reactive PF6, which reacts with the residual water and generates HF. In this paper, the adsorption and dissociation of H2O, HF, and PF5 on the Cu(111) surface were studied using a first-principles method based on the density functional theory. The stable configurations of HF, H2O, and PF5 adsorbed on Cu(111) and the geometric parameters of the admolecules were confirmed after structure optimization. The results showed that PF5 can promote the dissociation reaction of HF. Meanwhile, PF5 also promoted the physical adsorption of H2O on the Cu(111) surface. The CuF2 molecule was identified by determining the bond length and the bond angle of the reaction product. The energy barriers of HF dissociation on clean and O-atom-preadsorbed Cu(111) surfaces revealed that the preadsorbed O atom can promote the dissociation of HF significantly.

Structures, electronic properties and adsorption mechanisms of the O2Fe3N clusters

2019 ◽  
Vol 33 (19) ◽  
pp. 1950214 ◽  
Author(s):  
Zhen Zhao ◽  
Zhi Li
Keyword(s):  
Charge Transfer ◽  
Ground State ◽  
Magnetic Moments ◽  
Vertical Direction ◽  
Endothermic Reaction ◽  
Bridge Site ◽  
Adsorption Mechanisms ◽  
Kinetic Activity ◽  
Average Spin ◽  
State Formula

The structures, adsorption mechanisms and electronic attributes of the O2Fe3N clusters are calculated at Perdew, Burke and Ernzerhof (PBE) functional. The results show that two O atoms prefer to be located at the Fe–Fe bridge site of Fe–N molecule which form the ground-state O2Fe3N cluster, respectively. It means that O2 molecule is dissociated by Fe3N molecule. Compared to the isomer (3)–(6), it indicates that an O2 molecule is preferentially adsorbed on the top site of Fe atom which is close to N atom of the Fe3N molecule in the vertical direction. The adsorptions of Fe3N with O2 are the exothermic before endothermic reaction. All the O2Fe3N clusters possess higher kinetic activity. The average spin magnetic moments of the O2Fe3N clusters are as follows: isomer (6) [Formula: see text] isomer (1) [Formula: see text] isomer (3) [Formula: see text] isomer (5) [Formula: see text] ground-state [Formula: see text] isomer (2) [Formula: see text] isomer (4). Compared to the external charge transfer of the O2Fe3N clusters, the transfer of electrons between 4s and 3d, 4p orbitals in the same atom is significantly higher.

uMBD: A Materials-Ready Dispersion Correction that Uniformly Treats Metallic, Ionic, Covalent, and van der Waals Bonding

2019 ◽  
Author(s):  
Minho Kim ◽  
won june kim ◽  
Tim Gould ◽  
Eok Kyun Lee ◽  
Sébastien Lebègue ◽  
...  
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Electrode Materials ◽  
Full Range ◽  
Van Der Waals ◽  
Dft Method ◽  
Dispersion Correction ◽  
Computational Overhead ◽  
System A ◽  
Battery Design

<p>Materials design increasingly relies on first-principles calculations for screening important candidates and for understanding quantum mechanisms. Density functional theory (DFT) is by far the most popular first-principles approach due to its efficiency and accuracy. However, to accurately predict structures and thermodynamics, DFT must be paired with a van der Waals (vdW) dispersion correction. Therefore, such corrections have been the subject of intense scrutiny in recent years. Despite significant successes in organic molecules, no existing model can adequately cover the full range of common materials, from metals to ionic solids, hampering the applications of DFT for modern problems such as battery design. Here, we introduce a universally optimized vdW-corrected DFT method that demonstrates an unbiased reliability for predicting molecular, layered, ionic, metallic, and hybrid materials without incurring a large computational overhead. We use our method to accurately predict the intercalation potentials of layered electrode materials of a Li-ion battery system – a problem for which the existing state-of-the-art methods fail. Thus, we envisage broad use of our method in the design of chemo-physical processes of new materials.</p>

scholarly journals Dipole-induced Ohmic contacts between monolayer Janus MoSSe and bulk metals

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Ning Zhao ◽  
Udo Schwingenschlögl
Keyword(s):  
First Principles ◽  
Ohmic Contacts ◽  
Electrode Materials ◽  
Electronic Device ◽  
Two Dimensional ◽  
First Principles Calculations ◽  
Fermi Level Pinning ◽  
Common Electrode ◽  
Two Sides ◽  
Metallic Electrodes

AbstractUtilizing a two-dimensional material in an electronic device as channel layer inevitably involves the formation of contacts with metallic electrodes. As these contacts can dramatically affect the behavior of the device, we study the electronic properties of monolayer Janus MoSSe in contact with different metallic electrodes by first-principles calculations, focusing on the differences in the characteristics of contacts with the two sides of MoSSe. In particular, we demonstrate that the Fermi level pinning is different for the two sides of MoSSe, with the magnitude resembling that of MoS2 or MoSe2, while both sides can form Ohmic contacts with common electrode materials without any further adaptation, which is an outstanding advantage over MoS2 and MoSe2.

scholarly journals Study on Adsorption Properties of Modified Corn Cob Activated Carbon for Mercury Ion

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4483
Author(s):  
Yuyingnan Liu ◽  
Xinrui Xu ◽  
Bin Qu ◽  
Xiaofeng Liu ◽  
Weiming Yi ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Photoelectron Spectroscopy ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Raw Material ◽  
Order Kinetic ◽  
Mercury Ions ◽  
Corn Cob ◽  
Adsorption Time ◽  
X Ray

In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of mercury ions were undertaken. The results showed that when modified with KOH, the optimal adsorption time was 120 min, the optimum pH was 4; when modified with KMnO4, the optimal adsorption time was 60 min, the optimal pH was 3, and the optimal amount of adsorbent and the initial concentration were both 0.40 g/L and 100 mg/L under both modified conditions. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir model. Scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential characterization results showed that the adsorption process is mainly physical adsorption, surface complexation and ion exchange.

Modelling STM images of TiO2(110) from first-principles: Defects, water adsorption and dissociation products

2007 ◽  
Vol 437 (1-3) ◽  
pp. 73-78 ◽  
Author(s):  
G. Teobaldi ◽  
W.A. Hofer ◽  
O. Bikondoa ◽  
C.L. Pang ◽  
G. Cabailh ◽  
...  
Keyword(s):  
First Principles ◽  
Water Adsorption ◽  
Adsorption And Dissociation ◽  
Stm Images

First-Principles Study of Interaction of Lithium Atoms with (3, 3) Carbon Nanotubes

2014 ◽  
Vol 687-691 ◽  
pp. 4311-4314 ◽  
Author(s):  
Shun Fu Xu ◽  
Ling Min Li
Keyword(s):  
Carbon Nanotubes ◽  
First Principles ◽  
Density Functional ◽  
Vacancy Defect ◽  
Single Wall Carbon Nanotubes ◽  
Generalized Gradient ◽  
Hydrogen Atoms ◽  
Functional Theory ◽  
Vacancy Defects ◽  
Adsorption Mechanisms

In this paper, we have employed first-principles calculations to investigate the adsorption mechanisms of one lithium atom on the sidewalls of 1/2/3 H-adsorbed indefective/defective (3, 3) single-wall carbon nanotubes (CNTs) which have vacancy defects. Our calculations are performed within density functional theory (DFT) under the generalized gradient approximation (GGA) of Perdew, Burke, and Ernzerhof (PBE).Our results show that the lithium atoms strongly binds to the H-adsorbed (3, 3) nanotube. Lithium atoms can chemically adsorb on (3, 3) nanotube with the vacancy defect (MVD) without any energy barrier. The lithium adsorption will enhance the electrical conductivity of the nanotube. Further more, the structure of the (3, 3) nanotube with the MVD and hydrogen atoms will become more stable after the three kinds of lithium adsorption.

scholarly journals A chemical map of NaSICON electrode materials for sodium-ion batteries

2021 ◽  
Vol 9 (1) ◽  
pp. 281-292
Author(s):  
Baltej Singh ◽  
Ziliang Wang ◽  
Sunkyu Park ◽  
Gopalakrishnan Sai Gautam ◽  
Jean-Noël Chotard ◽  
...  
Keyword(s):  
Transition Metal ◽  
First Principles ◽  
Electrode Materials ◽  
Chemical Space ◽  
Sodium Ion ◽  
Sodium Ion Batteries ◽  
First Principles Calculations

Using first-principles calculations, we chart the chemical space of 3d transition metal-based NaSICON phosphates with the formula NaxMM′(PO4)3 (with M and M′ = Ti, V, Cr, Mn, Fe, Co and Ni). Novel NaSICON compositions were revealed.

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