First Principle Study of the Optical Properties of Transition Metal Nitrides XN (X=Ti, Zr, Hf)

The optical properties of face-centered cubic IVB group transition metal nitrides such as TiN, ZrN, and HfN were calculated using the plane wave pseudopotential method based on first-principle density function theory. The results of band structures show that conduction bands are mainly formed by the metal atom d-state, whereas valence bands are mainly formed by the N 2p-state. In optical properties research, the computed results of complex dielectric functions, absorptions, reflectivities, conductivities and loss functions of the three materials are analysed in terms of band structures. The results agree with experiment data. Analysis results show that the optical properties of these materials in low-energy regions are metallic because of the free electrons intraband-transition, and the transit to semiconducting properties in high-energy area is caused by valence electrons interband-transition. The sharp peaks of the transmissivity spectra indicate excellent optical selectivity in the visible light area. Moreover, lowering the starting energies of interband-transitions as a possible method to improve optical selectivities is discussed

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Density functional theory studies of structural, electronic and optical properties of cubic 3d-transition metal nitrides

Intermetallics ◽

10.1016/j.intermet.2021.107272 ◽

2021 ◽

Vol 137 ◽

pp. 107272

Author(s):

B.O. Mnisi ◽

E.M. Benecha ◽

M.M. Tibane

Keyword(s):

Density Functional Theory ◽

Optical Properties ◽

Transition Metal ◽

Density Functional ◽

Metal Nitrides ◽

Transition Metal Nitrides ◽

Functional Theory ◽

Electronic And Optical Properties

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First-Principles Study on Mechanical Properties of IVB-Group Transition-Metal Nitrides TiN, ZrN, and HfN

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.1451 ◽

2011 ◽

Vol 415-417 ◽

pp. 1451-1456

Author(s):

Jin Wang ◽

Zhi Qian Chen ◽

Chun Mei Li ◽

Fang Wang ◽

Ying Zhong

Keyword(s):

Mechanical Properties ◽

Transition Metal ◽

Elastic Properties ◽

Density Of States ◽

High Hardness ◽

Metal Nitrides ◽

Face Centered Cubic ◽

Transition Metal Nitrides ◽

Electronic Density ◽

Good Thermal Stability

IVB-group transition-metal nitrides are hot research materials due to their high hardness, good thermal stability, and excellent mechanical properties. In this paper, we studied the lattice parameters, elastic properties, electronic structures, and hardness of the face centered cubic TiN, ZrN, and HfN. The research shows that all the three types have excellent elastic properties. According to the result, elastic properties of HfN are the best of the three, as its bulk modulus and shear modulus are 278GPa and 240GPa respectively. With the calculation of electronic density of states, we find that all the three types are metallic. The wide pseudogap in DOS and the large overlap population indicate the strong Ti-N, Zr-N, and Hf-N bonds. The lower value of the density of states on the Fermi level shows that crystal structure of HfN is more stable. That is why the elastic properties of HfN are better than the others, mainly. The calculated hardness of TiN is 23.6GPa, which is the highest.

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Elastic and optical properties of IVB group transition-metal nitrides

Acta Physica Sinica ◽

10.7498/aps.62.087102 ◽

2013 ◽

Vol 62 (8) ◽

pp. 087102

Author(s):

Wang Jin ◽

Li Chun-Mei ◽

Ao Jing ◽

Li Feng ◽

Chen Zhi-Qian

Keyword(s):

Optical Properties ◽

Transition Metal ◽

Metal Nitrides ◽

Transition Metal Nitrides

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Recent Advances in the Electrocatalytic Application of Transition Metal Nitrides Nanocrystalline

10.20944/preprints202104.0504.v1 ◽

2021 ◽

Author(s):

Haolin Tang ◽

Shuhong Zheng ◽

Ren Luo

Keyword(s):

Transition Metal ◽

Noble Metals ◽

Electrode Materials ◽

Precious Metals ◽

High Energy ◽

High Energy Density ◽

Energy Storage And Conversion ◽

Metal Nitrides ◽

Transition Metal Nitrides ◽

Metal Atoms

The energy crisis and environmental problems are becoming more and more severe due to the long-term consumption of fossil fuels. Therefore, energy conversion devices with high energy density and environmental friendliness (such as fuel cells, metal-air batteries, etc.) have been ex-pected to be reliable alternatives to traditional fossil energy. However, due to the inevitable use of precious metals as the electrode catalysts for these devices, the popularization of these alternatives is seriously hindered. Transition metal nitrides (TMNs) exhibit similar surface and adsorption properties to noble metals since the atomic distance between metal atoms increases and the d-band center of metal atoms downshift after the nitrogen atoms enter the metal lattice. TMNs have become one of the best electrode materials to replace noble metal electrocatalysts in energy storage and conversion devices. In this review, the latest development in the electrocatalytic ap-plication of TMNs nanocrystalline is covered. Firstly, we briefly discuss the structure and activity origin of TMNs and introduce the common physical and chemical methods for the preparation of TMNs. Subsequently, we illustrate the applications of unary TMNs and multivariate TMNs in oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Finally, we summarize the challenges and problems of TMNs encountered at the present stage, and expect its future de-velopment.

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Stress-controlled decomposition routes in cubic AlCrN films assessed by in-situ high-temperature high-energy grazing incidence transmission X-ray diffraction

Scientific Reports ◽

10.1038/s41598-019-54307-7 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

M. Meindlhumer ◽

S. Klima ◽

N. Jäger ◽

A. Stark ◽

H. Hruby ◽

...

Keyword(s):

High Temperature ◽

Transition Metal ◽

Stress Level ◽

Grazing Incidence ◽

High Energy ◽

Metal Nitrides ◽

Transition Metal Nitrides ◽

X Ray Diffraction ◽

X Ray

AbstractThe dependence of decomposition routes on intrinsic microstructure and stress in nanocrystalline transition metal nitrides is not yet fully understood. In this contribution, three Al0.7Cr0.3N thin films with residual stress magnitudes of −3510, −4660 and −5930 MPa in the as-deposited state were in-situ characterized in the range of 25–1100 °C using in-situ synchrotron high-temperature high-energy grazing-incidence-transmission X-ray diffraction and temperature evolutions of phases, coefficients of thermal expansion, structural defects, texture as well as residual, thermal and intrinsic stresses were evaluated. The multi-parameter experimental data indicate a complex intrinsic stress and phase changes governed by a microstructure recovery and phase transformations taking place above the deposition temperature. Though the decomposition temperatures of metastable cubic Al0.7Cr0.3N phase in the range of 698–914 °C are inversely proportional to the magnitudes of deposition temperatures, the decomposition process itself starts at the same stress level of ~−4300 MPa in all three films. This phenomenon indicates that the particular compressive stress level functions as an energy threshold at which the diffusion driven formation of hexagonal Al(Cr)N phase is initiated, provided sufficient temperature is applied. In summary, the unique synchrotron experimental setup indicated that residual stresses play a decisive role in the decomposition routes of nanocrystalline transition metal nitrides.

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