Free-radical gases on two-dimensional transition-metal disulfides (XS2, X = Mo/W): robust half-metallicity for efficient nitrogen oxide sensors

The detection of single gas molecules is a highly challenging work because it requires sensors with an ultra-high level of sensitivity. By using density functional theory, here we demonstrate that the adsorption of a paramagnetic unpaired free radical gas (NO) on a monolayer of XS2 (X = Mo, W) can trigger the transition from semiconductor to half metal. More precisely, the single-layer XS2 (X = Mo, W) with NO adsorbed on it would behave like a metal in one spin channel while acting as a semiconductor in the other spin orientation. The half-metallicity is robust and independent of the NO concentration. In contrast, no half-metallic feature can be observed after the adsorption of other free radical gases such as NO2. The unique change in electronic properties after the adsorption of NO on transition-metal sulfides highlights an effective strategy to distinguish NO from other gas species by experimentally measuring spin-resolved transmission. Our results also suggest XS2 (X = Mo, W) nanosheets can act as promising nanoscale NO sensors.

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Magnetic properties of cobalt single layer added on graphene: A density functional theory study

Modern Physics Letters B ◽

10.1142/s0217984914502625 ◽

2015 ◽

Vol 29 (02) ◽

pp. 1450262 ◽

Cited By ~ 2

Author(s):

M. Afshar ◽

H. Doosti

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Single Layer ◽

Magnetic Ordering ◽

Polarization Degree ◽

Generalized Gradient ◽

Functional Theory ◽

Half Metallic ◽

Cobalt Layer ◽

Ferromagnetic Ordering

In this paper, we have demonstrated magnetic ordering of single cobalt layer added on graphene using relativistic density functional theory at the level of generalized gradient approximation. We have shown that the single Co layer added on graphene show ferromagnetic ordering with perpendicular alignment to the graphene sheet. In the presence of spin-orbit coupling, a spin-polarization degree of about 92% was found for this quasi-two-dimensional magnetic system where it is shown a nearly half-metallic feature.

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Pressure-Induced Tunable Magnetism and Half-Metallic Stability in Co2FeGa Heusler Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.477-478.1303 ◽

2013 ◽

Vol 477-478 ◽

pp. 1303-1306

Author(s):

Qin Xiang Gao

Keyword(s):

Fermi Level ◽

First Principles ◽

Density Functional ◽

High Energy ◽

First Principles Calculations ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Heusler Compound ◽

The Density Functional Theory

Using the first-principles calculations within the density functional theory (DFT), we have investigated the structure, magnetism and half-metallic stability of Co2FeGa Heusler compound under pressure from 0 to 50GPa. The results revel that the lattice constant is gradually shrank and total magnetic moment in per unit slightly decreased with increasing pressure, respectively. Moreover, with the increase of the pressure, the Fermi level will move towards high-energy orientation. When the pressure reaches at 30GPa the most stable half-metallicity is observed which the Fermi level is located at the middle of the spin-minority gap.

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Tunable Magnetism and Half-Metallic Stability in Si-Doped Hg2CuTi-Type Ti2CoGa Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.229-231.130 ◽

2012 ◽

Vol 229-231 ◽

pp. 130-133 ◽

Cited By ~ 2

Author(s):

Bo Wu ◽

Yu Feng ◽

Hong Kuan Yuan ◽

Hong Chen

Keyword(s):

Density Functional ◽

Magnetic Moments ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Lattice Constants ◽

Indirect Exchange ◽

The Density Functional Theory ◽

Si Doped ◽

Direct Hybridization

Using the ab-initio calculations within the density functional theory (DFT), we have investigated the electronic structure, magnetism and half-metallic stability of Si-doped Heusler compound Ti2CoGa with Hg2CuTi-type structure. The results revel that the lattice constants and total magnetic moments in per unit obey the Vegard’s rule and the Slater-Pauling rule well, respectively. The most stable half-metallicity occurs at doping concentration x=0.75 because the Fermi level is located at the middle of the spin-minority gap. Our studies also indicate that the competition between RKKY-type indirect exchange and direct hybridization of d-electronic atoms plays a dominating role in determining the magnetism.

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Infrared Spectra and Density Functional Theory Calculations of Group 4 Transition Metal Sulfides

The Journal of Physical Chemistry A ◽

10.1021/jp0202183 ◽

2002 ◽

Vol 106 (26) ◽

pp. 6295-6301 ◽

Cited By ~ 25

Author(s):

Binyong Liang ◽

Lester Andrews

Keyword(s):

Density Functional Theory ◽

Transition Metal ◽

Infrared Spectra ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Metal Sulfides ◽

Transition Metal Sulfides ◽

Functional Theory ◽

Group 4

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Theoretical Investigations on the Mechanical, Magneto-Electronic Properties and Half-Metallic Characteristics of ZrRhTiZ (Z = Al, Ga) Quaternary Heusler Compounds

Applied Sciences ◽

10.3390/app9050883 ◽

2019 ◽

Vol 9 (5) ◽

pp. 883 ◽

Cited By ~ 9

Author(s):

Wenbin Liu ◽

Xiaoming Zhang ◽

Hongying Jia ◽

Rabah Khenata ◽

Xuefang Dai ◽

...

Keyword(s):

Mechanical Properties ◽

Magnetic Moment ◽

Density Functional ◽

Total Magnetic Moment ◽

Heusler Compounds ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Theoretical Investigations ◽

Valence Electrons

The electronic, magnetic, and mechanical properties were investigated for ZrRhTiZ (Z = Al, Ga) quaternary Heusler compounds by employing first-principles calculations framed fundamentally within density functional theory (DFT). The obtained electronic structures revealed that both compounds have half-metallic characteristics by showing 100% spin polarization near the Fermi level. The half-metallicity is robust to the tetragonal distortion and uniform strain of the lattice. The total magnetic moment is 2 μB per formula unit and obeys the Slater-Pauling rule, Mt = Zt − 18 (Mt and Zt represent for the total magnetic moment and the number of total valence electrons in per unit cell, respectively). The elastic constants, formation energy, and cohesive energy were also theoretically calculated to help understand the possibility of experimental synthesis and the mechanical properties of these two compounds.

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Half-metallic ferromagnetism in hypothetical wurtzite structure chromium chalcogenides

Journal of Materials Research ◽

10.1557/jmr.2004.0347 ◽

2004 ◽

Vol 19 (9) ◽

pp. 2738-2741 ◽

Cited By ~ 3

Author(s):

Ming Zhang ◽

Ekkes Brück ◽

Frank R. de Boer ◽

Guodong Liu ◽

Haining Hu ◽

...

Keyword(s):

Density Functional ◽

Wurtzite Structure ◽

First Principle ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Principle Calculation ◽

First Principle Calculation ◽

Metallic Ferromagnetism ◽

Half Metallic Ferromagnetism

The hypothetical wurtzite structure chromium chalcogenides were investigated through first-principle calculation within density-functional theory. All compounds are predicted to be true half-metallic ferromagnets with an integer Bohr magneton of 4 μB per unit. Their half-metallic gaps are 1.147, 0.885, and 0.247 eV at their equilibrium volumes for wurtzite-type CrM (M = S, Se, and Te), respectively. The half-metallicity can be maintained even when volumes are expanded by more than 20% for all compounds and compressed by more than 20%, 20%, and 5%, for CrS, CrSe, and CrTe, respectively.

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Infrared Spectra and Density Functional Theory Calculations of Group 6 Transition Metal Sulfides in Solid Argon

The Journal of Physical Chemistry A ◽

10.1021/jp025915+ ◽

2002 ◽

Vol 106 (30) ◽

pp. 6945-6951 ◽

Cited By ~ 24

Author(s):

Binyong Liang ◽

Lester Andrews

Keyword(s):

Density Functional Theory ◽

Transition Metal ◽

Infrared Spectra ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Metal Sulfides ◽

Transition Metal Sulfides ◽

Functional Theory ◽

Group 6 ◽

Solid Argon

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First-Principle Calculations of Half-Metallic Double Perovskite La2BB´O6(B,B´=3d transition metal)

Communications in Computational Physics ◽

10.4208/cicp.190312.190712a ◽

2013 ◽

Vol 14 (1) ◽

pp. 174-185 ◽

Cited By ~ 13

Author(s):

Y. P. Liu ◽

S. H. Chen ◽

H. R. Fuh ◽

Y. K. Wang

Keyword(s):

Transition Metal ◽

Density Functional ◽

Double Perovskite ◽

Correlation Effect ◽

Generalized Gradient ◽

Functional Theory ◽

Half Metallic ◽

Generalized Gradient Approximation ◽

Full Structure ◽

Magnetic States

AbstractIn this paper, we present calculations based on density functional theory using generalized gradient approximation (GGA) in double perovskite structure La2BB’O6 (B,B’ = 3d transition metal) out of combinational possibilities. Considering 4 types of magnetic states, namely, ferromagnetic (FM), ferrimagnetic (FiM), antiferromagnetics (AF), and nonmagnetic (NM) with full structure optimization, 13 possible surviving, stable FM/FiM-HM materials containing 6 FM-HM materials (La2ScNiO6, La2CrCoO6, La2CrNiO6, La2VScO6, La2VZnO6, and La2VNiO6) and 7 FiM-HM materials (La2VFeO6, La2ZnCoO6, La2TiCoO6, La2CrZnO6, La2CrMnO6, La2ScFeO6, and La2TiMnO6) are found. Considering the correlation effect (GGA+U), there are 6 possible half-metallic stable, surviving (HM) materials containing 3 FMHM materials (La2ScNiO6, La2CrCoO6, and La2CrNiO6) and 3 FiM-HM materials (La2VFeO6, La2ZnCoO6, and La2TiCoO6).

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Tunable Magnetism and Half-Metallic Stability of Half-Heusler Compound NiMn1-xNbxSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1407 ◽

2011 ◽

Vol 415-417 ◽

pp. 1407-1410

Author(s):

Qing Zhou ◽

Bo Wu ◽

Hong Kuan Yuan ◽

Hong Chen

Keyword(s):

Density Functional ◽

Magnetic Moments ◽

Magnetic Coupling ◽

First Principles Calculations ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Heusler Compound ◽

Lattice Constants ◽

The Density Functional Theory

By using the first-principles calculations within the density functional theory (DFT), we investigate the electronic structure, magnetism and half-metallic stability of half-Heusler compound NiMn1-xNbxSb. The results showed that the lattice constants and magnetic moments per unit respectively follow the Vegard law and the Slater-Pauling rule well. The most stable half-metallicity occurs at doping concentration x=0.25 due to the Fermi level is situated the middle of the spin-down gap. Our studies also indicate that the competition of hybridization of d-electrons and RKKY-type magnetic coupling plays a dominating role in determining the magnetism.

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Electronic Structure and Magnetic Properties of Ga-Doped Heusler Alloy Co2FeSi

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.1430 ◽

2011 ◽

Vol 130-134 ◽

pp. 1430-1434 ◽

Cited By ~ 5

Author(s):

Yu Feng ◽

Bo Wu ◽

Hong Kuan Yuan ◽

Hong Chen

Keyword(s):

Electronic Structure ◽

Density Functional ◽

Doping Concentration ◽

Magnetic Moments ◽

Half Metallicity ◽

Functional Theory ◽

Half Metallic ◽

Heusler Compound ◽

Lattice Constants ◽

The Density Functional Theory

Using GGA+U (UCo=2.1eV, UFe=2.5eV) scheme based on the density functional theory (DFT), we investigate the electronic structure, magnetism and half-metallic stability of Ga-doped Heusler compound Co2FeSi. We find that the lattice constants and total magnetic moments in per unit respectively obey the Vegard’s rule and the Slater-Pauling rule well. The most stable half-metallicity occurs at doping concentration x=0.5 due to the Fermi level is situated slightly above the middle of the spin-down gap. Our studies also indicate that the RKKY-type exchange mechanism plays a dominating role in determining the magnetism of HMFs.

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