First-Principles Investigation of Ti2CSO and Ti2CSSe Janus MXene Structures for Li and Mg Electrodes

Functional Theory ◽

Energy Applications ◽

The Cost ◽

Lower Diffusion

<div> <div> <div> <p>While lithium battery electrodes are constantly being improved in terms of their properties, discovering new materials with alternative energy carriers like Mg are important to lower the cost of production and to enhance the energy density. MXenes are a type of highly investigated materials with promising energy applications due to their excellent electronic conductivity and good mechanical and dynamical stability. Experimentally realized Janus MoSSe nanosheets provided promising results for battery electrodes. It is known that the surface terminations of MXenes highly affect on the electrochemical properties and the diffusion barriers of ions. Inspired by this, we studied Ti2CSO and Ti2CSSe Janus MXenes for Li and Mg electrodes. Our density functional theory-based, first-principles calculations indicate that both monolayers are thermodynamically, mechanically, and dynamically stable. We calculated that the average voltages for Li and Mg adsorbed Ti2CST (T = O, Se) MXenes are approximately 0.95 and 0.2 V, respectively. The maximum voltage for Ti2CSTLix is about 2 V, and that for Ti2CSTMgx is around 0.45 V. The Mg adsorbed Ti2CSO monolayer exhibits the highest gravimetric capacity (524.54 mAh/g) compared to that of other Janus MXenes considered in this paper. For Ti2CSSeLix, we obtained a higher capacity (230.45 mAh/g) and a lower diffusion barrier (0.191 eV) than that of most of the Li adsorbed S-functionalized MXenes. </p> </div> </div> </div>

Thermodynamic Stability of Hexagonal and Rhombohedral Bn at Cvd Conditions from Van der Waals Corrected First Principles Calculations

10.26434/chemrxiv.8052218.v3 ◽

2019 ◽

Author(s):

Henrik Pedersen ◽

Björn Alling ◽

Hans Högberg ◽

Annop Ektarawong

Keyword(s):

Thin Films ◽

Thermodynamic Stability ◽

First Principles ◽

Thermal Equilibrium ◽

Density Functional ◽

Van Der Waals ◽

Chemical Vapor ◽

Functional Theory ◽

The Stability

Thin films of boron nitride (BN), particularly the sp<sup>2</sup>-hybridized polytypes hexagonal BN (h-BN) and rhombohedral BN (r-BN) are interesting for several electronic applications given band gaps in the UV. They are typically deposited close to thermal equilibrium by chemical vapor deposition (CVD) at temperatures and pressures in the regions 1400-1800 K and 1000-10000 Pa, respectively. In this letter, we use van der Waals corrected density functional theory and thermodynamic stability calculations to determine the stability of r-BN and compare it to that of h-BN as well as to cubic BN and wurtzitic BN. We find that r-BN is the stable sp<sup>2</sup>-hybridized phase at CVD conditions, while h-BN is metastable. Thus, our calculations suggest that thin films of h-BN must be deposited far from thermal equilibrium.

Hydrogenation and oxidation enhances the thermoelectric performance of Si2BN monolayer

New Journal of Chemistry ◽

10.1039/d0nj06000c ◽

2021 ◽

Author(s):

H. R. Mahida ◽

Deobrat Singh ◽

Yogesh Sonvane ◽

Sanjeev K. Gupta ◽

P. B. Thakor ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

First Principles ◽

Density Functional ◽

Thermoelectric Performance ◽

Functional Theory

In the present study, we have investigated the structural, electronic, and charge transport properties of pristine, hydrogenated, and oxidized Si2BN monolayers via first-principles calculations based on density functional theory (DFT).

Probing the electronic structures of Con (n = 1–5) clusters on γ-Al2O3 surfaces using first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06785a ◽

2017 ◽

Vol 19 (5) ◽

pp. 3679-3687 ◽

Cited By ~ 10

Author(s):

Tao Yang ◽

Masahiro Ehara

Keyword(s):

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Functional Theory

Using density functional theory calculations, we discussed the geometric and electronic structures and nucleation of small Co clusters on γ-Al2O3(100) and γ-Al2O3(110) surfaces.

Electronic structure of cubic BaTbO3 from first-principles pseudopotential calculations

Canadian Journal of Physics ◽

10.1139/p06-008 ◽

2006 ◽

Vol 84 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

G Y Gao ◽

K L Yao ◽

Z L Liu

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Pseudopotential Calculations ◽

Correlation Potential ◽

Density Contour

First-principles calculations of the electronic structure are performed for cubic BaTbO3 using the plane-wave pseudopotential method within the framework of density functional theory and using the generalized gradient approximation for the exchange-correlation potential. Our calculations show that cubic BaTbO3 is metallic, and that this metallic character is mainly governed by the Tb 4f electrons and the hybridization between the Tb 5d and O 2p states. From the analysis of the density of states, band structure, and charge density contour, we find that the chemical bonding between Tb and O is covalent while that between Ba and TbO3 is ionic. PACS Nos.: 71.15.Mb, 71.20.-b

Computational investigation of NH3 adsorption and dehydrogenation on a W-modified Fe(111) surface

Physical Chemistry Chemical Physics ◽

10.1039/c5cp05983f ◽

2015 ◽

Vol 17 (45) ◽

pp. 30598-30605 ◽

Cited By ~ 3

Author(s):

Ming-Kai Hsiao ◽

Chia-Hao Su ◽

Ching-Yang Liu ◽

Hui-Lung Chen

Keyword(s):

First Principles ◽

Density Functional ◽

Computational Investigation ◽

Functional Theory ◽

Nh3 Adsorption ◽

Tungsten Metal

We employed monolayer tungsten metal to modify the Fe(111) surface, denoted as W@Fe(111), and calculated the adsorption and dehydrogenation behaviors of NH3 on W@Fe(111) surface via first-principles calculations based on density functional theory (DFT).

Magnetism and Half-Metallicity in (100) Surface of Inverse Heusler Mn2CoSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.377 ◽

2014 ◽

Vol 1015 ◽

pp. 377-380

Author(s):

Tao Chen ◽

Ying Chen ◽

Yin Zhou ◽

Hong Chen

Keyword(s):

Magnetic Properties ◽

First Principles ◽

Heusler Alloy ◽

Density Functional ◽

Magnetic Moments ◽

Surface States ◽

Half Metallicity ◽

Functional Theory

Using the first-principles calculations within density functional theory (DFT), we investigated the electronic and magnetic properties of (100) surface of inverse Heusler alloy Mn2CoSb with five different terminations. Our work reveals that the surface Mn atom moves to vacuum while surface Co atom moves to slab. Moreover, duo to the reason that the surface atom lost half of the nearest atoms with respect to the bulk phase, resulting in the decrease of hybridization, the atom-resolved spin magnetic moments of surface atoms are enhanced. Further investigation on DOS and PDOS showed that half-metallicity was preserved only in SbSb-termination while was destroyed in MnCo-, MnSb-, MnMn-, and CoCo-termination due to the appearance of surface states.

First-principles study of static displacements in Fe-Pd magnetic shape-memory alloys

MRS Proceedings ◽

10.1557/proc-1200-g04-04 ◽

2009 ◽

Vol 1200 ◽

Cited By ~ 1

Author(s):

Markus E. Gruner

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

Magnetic Shape Memory ◽

Magnetic Shape Memory Alloys ◽

Functional Theory ◽

Lennard Jones ◽

Theory Comparison

AbstractThis contribution reports static ionic displacements in ferromagnetic disordered Fe70Pd30 alloys obtained by relaxation of the ionic positions of a 108-atom supercell within the framework of density functional theory. Comparison with a simple statistical model based on Lennard-Jones pair interactions reveals that these displacements are significantly larger than can be explained by the different sizes of the elemental constituents. The discrepancies are presumably related to collective displacements of the Fe atoms. Corresponding distortions are experimentally observed for ordered Fe3Pt and predicted by first-principles calculations for all ordered Fe-rich L12 alloys with Ni group elements and originate from details of the electronic structure at the Fermi level.

Electronic, optical and thermoelectric properties of Fe2ZrP compound determined via first-principles calculations

RSC Advances ◽

10.1039/c9ra04736k ◽

2019 ◽

Vol 9 (44) ◽

pp. 25900-25911 ◽

Cited By ~ 3

Author(s):

Esmaeil Pakizeh ◽

Jaafar Jalilian ◽

Mahnaz Mohammadi

Keyword(s):

Thermoelectric Properties ◽

First Principles ◽

Density Functional ◽

Transport Theory ◽

Boltzmann Transport ◽

Functional Theory ◽

Boltzmann Transport Theory ◽

The Density Functional Theory

In this study, based on the density functional theory and semi-classical Boltzmann transport theory, we investigated the structural, thermoelectric, optical and phononic properties of the Fe2ZrP compound.

Effect of Defects on Spontaneous Polarization in Pure and Doped LiNbO3: First-Principles Calculations

Materials ◽

10.3390/ma12010100 ◽

2018 ◽

Vol 12 (1) ◽

pp. 100 ◽

Cited By ~ 5

Author(s):

Weiwei Wang ◽

Dahuai Zheng ◽

Mengyuan Hu ◽

Shahzad Saeed ◽

Hongde Liu ◽

...

Keyword(s):

Spontaneous Polarization ◽

First Principles ◽

Density Functional ◽

Lattice Distortion ◽

Stable Structure ◽

Functional Theory ◽

The Density Functional Theory ◽

Specific Configuration ◽

The Relationship

Numerous studies have indicated that intrinsic defects in lithium niobate (LN) dominate its physical properties. In an Nb-rich environment, the structure that consists of a niobium anti-site with four lithium vacancies is considered the most stable structure. Based on the density functional theory (DFT), the specific configuration of the four lithium vacancies of LN were explored. The results indicated the most stable structure consisted of two lithium vacancies as the first neighbors and the other two as the second nearest neighbors of Nb anti-site in pure LN, and a similar stable structure was found in the doped LN. We found that the defects dipole moment has no direct contribution to the crystal polarization. Spontaneous polarization is more likely due to the lattice distortion of the crystal. This was verified in the defects structure of Mg2+, Sc3+, and Zr4+ doped LN. The conclusion provides a new understanding about the relationship between defect clusters and crystal polarization.