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Schematic diagram (cross section) of shock-recovery experiments. The dimensions of the target copper container are diameter: 30 mm, length: 30 mm.
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Since the discovery of spinel nitrides in 1999, there has been a lot of effort in basic science to further develop advanced nitrides and electronic nitrides. The aim and scope of the research in this field is to synthesize novel nitrides for structural and functional applications. Silicon-based spinel nitrides combine ultrahigh hardness with high t...
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... shock recovery experiments, a projectile with a met- al flyer (e.g., copper) is accelerated by a propellant gun to a required velocity and impacts the target metal container (e.g., copper). Flat-impact methods using guns (Fig. 10) allow for an easy estimation of the shock pressure by the impedance- match method from a measured impact velocity. [131] The tem- perature estimation is based on the thermodynamic back- ground and subject to variations due to the porosity and pore distribution in the initial powder sample. In shock-synthesis experiments, the use of a ...
Citations
... Ternary nitrides are a burgeoning materials class hosting diverse structures, compositions, and properties that make them appealing for various applications [1]. Most of this research focuses on semiconducting and metallic nitrides for optoelectronic, piezoelectric, lighting, and structural applications, harnessing their cation-tunable electronic structures and superior mechanical properties [2][3][4][5][6]. However, discovery of novel ternary nitrides in new compositions is challenging owing to difficulty in breaking the strong molecular dinitrogen bonds and overcoming thermodynamic driving forces that favor simpler binary nitrides. ...
MnSiN2 is a transition-metal nitride with Mn and Si ions displaying an ordered distribution on the cation sites of a distorted wurtzite-derived structure. The Mn2+ ions reside on a three-dimensional (3D) diamondlike covalent network with strong superexchange pathways. We simulate its electronic structure and find that the N anions in MnSiN2 act as σ- and π-donors, which serve to enhance the N-mediated superexchange, leading to the high Néel ordering temperature of TN = 443 K. Polycrystalline samples of MnSiN2 were prepared to reexamine the magnetic structure and resolve previously reported discrepancies. An additional magnetic canting transition is observed at Tcant = 433 K and the precise canted ground-state magnetic structure has been resolved using a combination of density functional theory (DFT) calculations and powder neutron diffraction. The calculations favor a G-type antiferromagnetic spin order with lowering to Pc′. Irreducible representation analysis of the magnetic Bragg peaks supports the lowering of the magnetic symmetry. The computed model includes a 10∘ rotation of the magnetic spins away from the crystallographic c axis consistent with measured powder neutron diffraction data modeling and a small canting of 0.6∘.
... Also, such data are useful by establishing relationships between elastic moduli and hardness of a large variety of materials, in general, e.g. [21] or within the family of spinel nitrides, γ-M 3 N 4 where M = Si, Ge or Sn [20,22]. ...
... Thus, the BLS-peak asymmetry should result in an overestimation of the LW velocity by 4.1% and 3.3%, respectively. Applying the latter value, we corrected the product n · V L,0 from our BLS measurement to 22 V L , 0 = 9.3(4) km s −1 from our LU measurements, we determined the refractive index of γ-Ge 3 N 4 to be n = 2.4(1) at λ = 532 nm. This experimental value is very similar to our theoretical n = 2.46 derived from the dependence n(λ) calculated in the wavelength region of visible light ( figure 4). Figure 4 also shows the wavelength-dependent absorption coefficient of γ-Ge 3 N 4 , κ(λ), which predicts transparency of γ-Ge 3 N 4 at λ > 360 nm corresponding to the photon energy h · ν = 3.44 eV. ...
Germanium nitride, having cubic spinel structure, γ-Ge3N4, is a wide band-gap semiconductor with a large exciton binding energy that exhibits high hardness, elastic moduli and elevated thermal stability up to approximately 700°C. Experimental data on its bulk and shear moduli (B0 and G0, respectively) are strongly limited, inconsistent and, thus, require verification. Moreover, earlier first-principles density functional calculations provided significantly scattering B0 values but consistently predicted G0 much higher than the so far available experimental value. Here, we examined the elasticity of polycrystalline γ-Ge3N4, densified applying high pressures and temperatures, using the techniques of laser ultrasonics (LU) and Brillouin light scattering (BLS) and compared with our extended first-principles calculations. From the LU measurements, we obtained its longitudinal- and Rayleigh wave sound velocities and, taking into account the sample porosity, derived B0 = 322(44) GPa and G0 = 188(7) GPa for the dense polycrystalline γ-Ge3N4. While our calculations underestimated B0 by approximately 17%, most of the predicted G0 matched well with our experimental value. Combining the LU- and BLS data and taking into account the elastic anisotropy, we determined the refractive index of γ-Ge3N4 in the visible range of light to be n = 2.4, similarly high as that of diamond or GaN, and matching our calculated value.
This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 1)'.
... Nitrides of the group 14 elements having spinel structure, γ -M 3 N 4 (where M = Si, Ge or Sn), and their solid solutions [1][2][3][4][5] are promising multi-functional materials which are not only hard and stiff [6][7][8][9][10][11][12][13] but have been predicted to exhibit interesting optoelectronic properties 2023 The Author(s) Published by the Royal Society. All rights reserved. ...
We report on the synthesis of tin(IV) nitride with spinel structure, γ-Sn3N4, from the elements at high pressures and temperatures using a laser-heated diamond anvil cell, and on the Rietveld refinement of the product structure. The procedure described here is, in our opinion, the most reliable method of obtaining high-purity nitrides which are thermodynamically stable only at high pressures. Raman spectroscopy and powder X-ray diffraction were used to characterize the synthesis products. Pressure dependences of the Raman-band frequencies of γ-Sn3N4 were measured and used to determine its average mode Grüneisen parameter, 〈γ〉 = 0.95. Using this value, we estimated the thermal-shock resistance of γ-Sn3N4 to be about half that of γ-Si3N4, which, in turn, is moderately surpassed by β-Si3N4, known to be highly thermal-shock resistant.
This article is part of the theme issue ‘Exploring the length scales, timescales and chemistry of challenging materials (Part 1)’.
... Ternary nitrides are a burgeoning materials class hosting diverse structures, compositions, and properties that make them appealing for various applications [1]. Most of this research focuses on semiconducting and metallic nitrides for optoelectronic, piezoelectric, lighting, and structural applications, harnessing their cation-tunable electronic structures and superior mechanical properties [2][3][4][5][6]. However, discovery of novel ternary nitrides in new compositions is challenging owing to difficulty in breaking the strong molecular dinitrogen bonds and overcoming thermodynamic driving forces that favor simpler binary nitrides. ...
MnSiN$_2$ is a transition metal nitride with Mn and Si ions displaying an ordered distribution on the cation sites of a distorted wurtzite-derived structure. The Mn$^{2+}$ ions reside on a 3D diamond-like covalent network with strong superexchange pathways. We simulate its electronic structure and find that the N anions in MnSiN$_2$ act as $\sigma$- and $\pi$-donors, which serve to enhance the N-mediated superexchange, leading to the high N\'{e}el ordering temperature of $T_N$ = 443 K. Polycrystalline samples of MnSiN$_2$ were prepared to reexamine the magnetic structure and resolve previously reported discrepancies. An additional magnetic canting transition is observed at $T_\mathrm{cant}$ = 433 K and the precise canted ground state magnetic structure has been resolved using a combination of DFT calculations and powder neutron diffraction. The calculations favor a $G$-type antiferromagnetic spin order with lowering to $Pc^\prime$. Irreducible representation analysis of the magnetic Bragg peaks supports the lowering of the magnetic symmetry. The computed model includes a 10$^\circ$ rotation of the magnetic spins away from the crystallographic $c$-axis consistent with measured powder neutron diffraction data modeling and a small canting of 0.6$^\circ$.
... For example, in terms of hardness, many investigations have been carried out to create materials that match or exceed the hardness of diamonds. In this regard, cubic boron nitride (c-BN) and aluminum oxynitride (γ-AlON) which have spinel structures are considered the most famous compounds as they are characterized by their high hardness in addition to their use in many applications [11,12]. The high transparency, hardness, and durability of oxynitrides make them suitable for military and commercial applications such as missile domes, armor, lenses, cellphone screens, and point-of-sale scanner windows. ...
... Boron oxynitride's (BON) physical and chemical properties have been studied theoretically and experimentally, mainly focused on the hardness property. For example, it was found that the structural models with the lowest formation enthalpies have predicted bulk modules of about 300 GPa for B 6 N 4 O 3 which are larger than those of any other known oxynitride [11,17]. Moreover, several studies demonstrated that hexagonal boron nitride (h-BN) is suitable for use in optoelectronic devices for deep ultraviolet (DUV) materials [18,19]. ...
... For example, in terms of hardness, many investigations have been carried out to create materials that match or exceed the hardness of diamonds. In this regard, cubic boron nitride (c-BN) and aluminum oxynitride (γ-AlON) which have spinel structures are considered the most famous compounds as they are characterized by their high hardness in addition to their use in many applications [11,12]. The high transparency, hardness, and durability of oxynitrides make them suitable for military and commercial applications such as missile domes, armor, lenses, cellphone screens, and point-of-sale scanner windows. ...
... Boron oxynitride's (BON) physical and chemical properties have been studied theoretically and experimentally, mainly focused on the hardness property. For example, it was found that the structural models with the lowest formation enthalpies have predicted bulk modules of about 300 GPa for B 6 N 4 O 3 which are larger than those of any other known oxynitride [11,17]. Moreover, several studies demonstrated that hexagonal boron nitride (h-BN) is suitable for use in optoelectronic devices for deep ultraviolet (DUV) materials [18,19]. ...
... Transition metal nitride (MN x , M represents transition metal) thin films are well known as a class of fascinating and technologically important materials in the fields of electronic devices, cutting-and machining-tool industry [1][2][3][4][5]. Among them, zirconium nitride (ZrN x ) thin films have been intensively studied in temperature sensing due to their good performance such as wide temperature ranges, minimal dependence on magnetic field and high temperature sensitivity. ...
MOxNy (M represents transition metal) thin films have shown excellent performance in various fields such as temperature sensing, high-k gate dielectrics and decorative coatings. Thin film properties can be significantly affected by adjusting oxygen contents, while the physical mechanism of oxygen in MNx structure is not well explored. In this paper, the effects of oxygen doping in ZrN thin films (expressed as ZrOxNy) on material modification and temperature sensing are discussed from a viewpoint of Zr vacancies (VZr). A phenomenon of phase transition from ZrN into Zr3N4 structure is observed with increasing flow rates of N2/O2 in thin film deposition. In addition, an electronic transition from metallic to semiconductor behavior is found even a slight oxygen is doped in ZrN structure. Based on the experimental results and first principal calculations, a physical model is proposed that VZr can be induced in ZrN structure by oxygen doping. A small quantity of VZr change the electronic behavior of the film from metallic to semiconductor type and a large quantity trigger phase transition from ZrN to Zr3N4 structure. The results and model provide clear insights into engineering of ZrOxNy thin films for high performance temperature sensors.
Graphical Abstract
... The Diamond Anvil Cell (DAC) technique can also be used to fabricate high-pressure ceramics. 130,131 Lower liquid originates less precision of the mold filling, which needs high forming pressure, and drying also helps to reduce cracking failure, while increasing the size of the substance also increases the risk of cracking failure. The sintering operation is performed by combining the interconnective bonding of all ceramic particles when heat treatment with the primary objective is actually to achieve a dimensionally accurate dense product. ...
... Properties of Various ceramic materials. 120,128,130,131,145, Type of ceramic for synthesizing and fabrications which are ease to use for industrial production. In this comprehensive review, we specifically summarize all previous works of experimental findings and present various beneficiary aspects of future ceramics implementation process with more beneficial attributes. ...
In the era of biomaterials evolution, ceramic materials are playing a notable role in dental practices. Ceramics have been used in dental applications for several decades because of its important properties such as suitable biological incorporation into human body, surface colouration, enhanced surface morphology, mechanical characteristics, physiochemical integration, durability and lifespan. There are numerous complications in the fabrication and production of ceramics by manufacturers. Therefore, much research and development has been performed to further improve and understand the manufacturing mechanisms which occur on the ceramic materials. These efforts are aimed at not only improving the fundamental understanding of the material but also helping to meet customer satisfaction and quality of production. This review article mainly provides insight on the various ceramic materials with a focus on their properties including stability, strength, and heat resistance. It is corroborated with a detailed account of various ceramic fabrication processing techniques with their applications that include sol-gel casting, hot pressing and phase inversion methods. In summary, some critical suggestions as well as detailed scope of future aspects and frontiers have been outlined to provide robust improvements for research and development platforms.
... As such, TMNAs are usually hard or potentially superhard materials with outstanding chemical inertness. For example, as a group of classical hard materials, transition-metal mononitrides, such as TiN, CrN, WN, HfN, and ZrN, are used as coating or covering layers for cutting tools to process ferrous alloys because of their remarkable stability [41][42][43][44][71][72][73][74][75][76]. Some TMNAs are superconductors [33], and some possess unusual magnetic properties [77], making them good candidate materials for unraveling fundamental physics. ...
... TMNAs in recent years have drawn significant attention due to their fundamental and technological importance [41][42][43][44][71][72][73][74][75][76]. They are characterized by strong covalent bonds between nitrogen atoms and polar covalent bonds between transition-metal and nitrogen atoms. ...
... As such, TMNAs are usually hard or potentially superhard materials with outstanding chemical inertness. For example, as a group of classical hard materials, transition-metal mononitrides, such as TiN, CrN, WN, HfN, and ZrN, are used as coating or covering layers for cutting tools to process ferrous alloys because of their remarkable stability [41][42][43][44][71][72][73][74][75][76]. Some TMNAs are superconductors [33], and some possess unusual magnetic properties [77], making them good candidate materials for un-raveling fundamental physics. ...
Nitride materials including conventional manmade superhard light-element nitrides, such as cubic boron nitride (cBN), cubic silicon nitride (γ-Si3N4), and carbonitrides, have been extensively used for machining (e.g., turning, cutting, grinding, boring, drilling) and coating of ferrous alloys due to their remarkable performances of high rigidity, high melting-point, and prominent chemical and thermal stabilities. However, to some degree, superhard nitrides merely compensate for the adverse limitations of diamond: reaction (with iron), oxidation, and graphitization at moderate temperatures; they are still unable to dominate the market owing to their relatively low hardness when compared to diamond. Therefore, recent efforts toward the preparation of nitride materials with outstanding mechanical performance and chemical inertness have focused on synthesizing ternary light-element nitride compounds and harvesting the effect of work hardening through microstructure manipulations. These new light-element nitrides are potential candidates to displace diamond in the cutting business. On the other hand, incorporation of transition-metal atoms into the dinitrogen triple-bond can form novel hard transition-metal nitride alloys (TMNAs), such as Mo-N, W-N, Pt-N, Ir-N, Os-N, etc., which are potential candidates for the cutting, coating, and polishing of iron-group metals. However, synthesis of high-crystallinity and stoichiometric TMNAs via traditional routes is challenging, since the embedded nitrogen in the transition-metal lattice is thermodynamically unfavorable at ambient condition. A novel approach involving ionexchange reactions under moderate pressure and temperature has been developed in recent years for preparation of well-crystallized stoichiometric TMNAs, which have quickly been realized as emergent materials in electronics, catalysts, and superconductors as well.
... Germanium(IV) nitride having spinel structure is one of the members of the family of spinel nitrides of the group 14 elements (-M 3 N 4 where M=Si, Ge, Sn) discovered two decades ago [1][2][3]. As any high-pressure non-conducting material, γ-Ge 3 N 4 exhibits high elastic moduli and hardness, [4]; it is also thermally (meta)stable at atmospheric pressure to ~700 ºC [5]. ...
Electronic band structure in germanium nitride having spinel structure, γ-Ge3N4, was examined using two spectroscopic techniques, cathodoluminescence and synchrotron-based photoluminescence. The sample purity was confirmed by x-ray diffraction and Raman analyses. The spectroscopic measurements provided first experimental evidence of a large free exciton binding energy De≈0.30 eV and direct interband transitions in this material. The band gap energy Eg = 3.65 ± 0.05 eV measured with a higher precision was in agreement with that previously obtained via XES/XANES method. The screened hybrid functional Heyd–Scuseria–Ernzerhof (HSE06) calculations of the electronic structure supported the experimental results. Based on the experimental data and theoretical calculations, the limiting efficiency of the excitation conversion to light was estimated and compared with that of w-GaN, which is the basic material of commercial light emitting diodes. The high conversion efficiency, very high hardness and rigidity combined with a thermal stability in air up to ~ 700 °C reveal the potential of γ-Ge3N4 for robust and efficient photonic emitters.Graphic abstract
