Journal articles: 'Nitrides'

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Van Landeghem, Hugo, Raphaële Danoix, Mohamed Gouné, Sylvie Bordère, Andrius Martinavičius, Peter Jessner, Thierry Epicier, Béatrice Hannoyer, Frédéric Danoix, and Abdelkrim Redjaïmia. "Contribution of Local Analysis Techniques for the Characterization of Iron and Alloying Elements in Nitrides: Consequences on the Precipitation Process in Fe–Si and Fe–Cr Nitrided Alloys." Materials 11, no. 8 (August 11, 2018): 1409. http://dx.doi.org/10.3390/ma11081409.

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Atom Probe Tomography (APT), Transmission Electron Microscopy (TEM), and 3D mechanical calculations in complex geometry and anisotropic strain fields were employed to study the role of minor elements in the precipitation process of silicon and chromium nitrides in nitrided Fe–Si and Fe–Cr alloys, respectively. In nitrided Fe–Si alloys, an original sequence of Si3N4 precipitation was highlighted. Al–N clusters form first and act as nucleation sites for amorphous Si3N4 nitrides. This novel example of particle-simulated nucleation opens a new way to control Si3N4 precipitation in Fe–Si alloys. In nitrided Fe–Cr alloys, both the presence of iron in chromium nitrides and excess nitrogen in the ferritic matrix are unquestionably proved. Only a certain part of the so-called excess nitrogen is shown to be explained by the elastic accommodation of the misfit between nitride and the ferritic matrix. The presence of immobile excess nitrogen trapped at interfaces can be highly suspected.

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Wołowiec-Korecka, Emilia, Jerzy Michalski, and Bartłomiej Januszewicz. "The Stability of the Layer Nitrided in Low-Pressure Nitriding Process." Coatings 13, no. 2 (January 21, 2023): 257. http://dx.doi.org/10.3390/coatings13020257.

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The kinetics of the nitrided layer thickness growth and its structure depend on the nitrogen flux from the atmosphere to the nitrided surface. A nitrogen flux to the surface is more significant than a diffusion flux into the substrate, during forming surface iron nitrides and the internal nitriding zone. For pure iron, nitrided under low pressure, cutting off the nitriding atmosphere creates a flux from the subsurface layer of nitrides to the surface. The purpose of this paper is to determine the direction of the nitrogen flux in a similar situation for steels containing nitride-forming elements, thus answering the question of the stability of the layer nitrided under such conditions. The surface of X37CrMoV5-1 steel was nitrided under low pressure (of 24 hPa) and annealed in a vacuum or nitrogen. The microstructure, thickness of the nitride layers nitrided layers, the thickness of the internal nitriding zone, surface hardness and stresses were examined. The highest values of the nitrided layer properties were observed for the samples saturated only with nitrogen obtained from ammonia dissociation or additionally heated in nitrogen. It has been shown that using a pure vacuum during the annealing stage leads to unfavourable changes in the structure of the nitrided layer formed and, in particular, to the decomposition of the iron nitride layer formed at the saturation stage and occurrence of the tensile stresses—what excludes practical application of such layer. Ultimately, it has been shown that in the low-pressure nitriding process, the stability of the nitride layer of the nitrided surface strongly depends on the annealing atmosphere during the annealing stage, while the stability of the internal nitriding zone remains mainly at the same level.

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Shabashov, V. A., S. V. Afanasiev, V. A. Zavalishin, L. G. Korshunov, S. V. Borisov, A. V. Litvinov, A. E. Zamatovsky, and V. A. Semionkin. "Implementation of Megaplastic Deformation for Control of the Gradient Composition of Pseudo-Layers in the Nitrided Surface of Fe-Ni-Cr Steel - Production of Quasi-Bimetallic Plate." Defect and Diffusion Forum 371 (February 2017): 86–96. http://dx.doi.org/10.4028/www.scientific.net/ddf.371.86.

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Megaplastic deformation has been realized by sliding friction (or high-pressure torsion) on ion-plasma-nitrided surface of austenitic Fe-Cr-Ni steel. The deformation-induced dissolution of iron and chromium nitrides, the formation of secondary chromium nitride phases and the increase of depth of gradient-composition matrix pseudo-layer have been achieved under friction and subsequent annealing. A quasi-bimetallic foil with the largest dimension of deflection has been produced with the use of friction and subsequent annealing of the nitrided surface.

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Riedel, Ralf, Elisabeta Horvath-Bordon, Hans Joachim Kleebe, Peter Kroll, G. Miehe, P. A. van Aken, and Stefan Lauterbach. "New Ceramic Phases in the Ternary Si-C-N System." Key Engineering Materials 403 (December 2008): 147–48. http://dx.doi.org/10.4028/www.scientific.net/kem.403.147.

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The ultra-high pressure and temperature synthesis of spinel silicon nitride and germanium nitride on the one hand as well as the successful synthesis of tin nitride at ambient pressure on the other hand have caused an enormous impact on both basic science and technological development of advanced nitrides. Aim and scope of the research in this field is to synthesize novel nitrides for structural and functional applications. High presssure nitrides may combine ultra-high hardness with high thermal stability in terms of decomposition in different environments and are expected to show interesting optoelectronic properties. Here, the state of the art and the progress in the field of novel advanced nitrides and related materials synthesized reproducibly under high pressure are reviewed.

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Petrova, Larisa, Vladimir Alexandrov, Viktor Vdovin, and Pyotr Demin. "Hardening of a quick-speed steel tool through nitration process with nitrogen controlled potential." Science intensive technologies in mechanical engineering 2022, no. 1 (January 28, 2022): 3–10. http://dx.doi.org/10.30987/2223-4608-2022-1-3-10.

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The study of the gas nitriding method, which allows obtaining high-quality diffuse layers in high-speed steel P6M5 on the basis of an internal nitrogen hardening zone with no brittle nitride zone, has been viewed. Research results of phase composition of nitrided steel with a change in the nitrogen potential of the atmosphere during dilution of ammonia are presented. Nitrided tool increased resistance during drilling constructional steel and titanium alloy, which is due to precipitation hardening treatment of the internal nitrogenization zone using tungsten nitrides, is given.

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Mondal, S., and A. K. Banthia. "Triethanolamine Molybdate, a New Polymeric Precursor for Molybdenum Nitride." Advanced Materials Research 29-30 (November 2007): 195–98. http://dx.doi.org/10.4028/www.scientific.net/amr.29-30.195.

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Nitrides remain a relatively unexplored class of materials primarily due to the difficulties associated with their synthesis and characterization. Several synthetic routes, including high temperature reactions, microwave assisted synthesis, and the use of plasmas, to prepare binary and ternary nitrides have been explored. Transition metal nitrides form a class of materials with unique physical properties, which give them varied applications, as high temperature ceramics, magnetic materials, superconductors or catalysts. They are commonly prepared by high temperature conventional processes, but alternative synthetic approaches have also been explored, more recently, which utilize moderate temperature condition. Transition metal nitrides particularly, molybdenum nitride, niobium nitride, and tungsten nitride have important applications as catalyst in hydrodenitridation reactions. These nitrides have been traditionally synthesized using high temperature nitridation treatments of the oxides. The nitridation temperatures are very high (> 800- 1000 oC). The aim of our work is to synthesize molybdenum nitride by a simple, low-temperature route. The method involves pyrolysis of a polymeric precursor, which was prepared from the condensation reaction between triethanolamine and molybdic acid. The melting point of the product is 180oC. The polymeric precursor and its pyrolyzed products are characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). X-ray diffraction shows that molybdenum nitride (MoN) obtained from this method has hexagonal crystal structure. MoN is obtained by this method at very low temperature (~ 400 oC).

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Novák, Pavel, Dalibor Vojtěch, Jan Šerák, Michal Novák, and Barbora Bártová. "Mechanism and Kinetics of Plasma Nitriding of the Nb-Alloyed PM Tool Steel." Defect and Diffusion Forum 263 (March 2007): 87–92. http://dx.doi.org/10.4028/www.scientific.net/ddf.263.87.

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The aim of this work was to describe the mechanism and kinetics of plasma nitriding of a Nb-containing PM (powder metallurgy) tool steel. Material containing 2.5 wt.% C, 3.3% Si, 6.2% Cr, 2.2% Mo, 2.6% V, 2.6% Nb and 1.0% W was prepared by nitrogen melt atomization and hot isostatic pressing. Heat-treated steel (quenching from 1100 °C, triple tempering at 550 °C for 1h) was plasma nitrided at temperatures ranging from 470 °C to 530 °C / 30 - 180 min. Light microscopy, TEM, SEM and WDS were used to study the nitrided steel. It has been shown, that nitriding at 470°C leads to the formation of thin layers composed only of a diffusion zone containing nitrogen-rich martensite and fine nitride precipitates, no layer of nitrides is formed on the surface. Nitriding is probably controlled by the nitrogen diffusion in martensite to the material or by the processes in the nitriding atmosphere at this temperature. Nitriding at the temperature of 500°C and more leads to the formation of a continuous layer of nitrides and carbonitrides on the surface that limits further nitrogen diffusion. Niobium, as a prospective element in tool steels, was not found to play a role in the formation of the nitrided layer directly. Niobium replaces vanadium in very thermodynamically stable primary MC carbides. This results in higher vanadium content in others less stable carbides and in the matrix. Due to this effect, higher portion of vanadium can precipitate as VC carbides and VN nitrides during heat treatment and nitriding, respectively.

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Schwarz, Benjamin, Regina E. Hörth, Ewald Bischoff, Ralf E. Schacherl, and Eric J. Mittemeijer. "The Process of Tungsten-Nitride Precipitation upon Nitriding Ferritic Fe-0.5 at.% W Alloy." Defect and Diffusion Forum 334-335 (February 2013): 284–89. http://dx.doi.org/10.4028/www.scientific.net/ddf.334-335.284.

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The precipitation of tungsten nitride upon internal nitriding of ferritic Fe-0.5 at.% W alloy was investigated at 610°C in a flowing NH3/H2 gas mixture. Different tungsten nitrides developed successively; the thermodynamically stable hexagonal δ-WN could not be detected. The state of deformation of the surface plays an important role for the development of tungsten nitride at the surface. The morphologies of the tungsten nitrides developed at the surface and those precipitated at some depth in the specimen are different. The nitride particles at the surface exhibit mostly an equiaxed morphology (with the size of the order 0.5 µm) and have a crystal structure which can be described as a superstructure derived from hexagonal δ-WN. These nitride particles show a strong preferred orientation with respect to the specimen frame of reference but have no relation with the crystal orientation of the surrounding ferrite matrix. In the bulk, nanosized and finely dispersed platelet-like precipitates grow preferentially along {100}α-Fe. It is unclear whether these precipitates consist of binary iron nitride α´´-Fe16N2 or of a ternary Fe-W-N. Additionally to the finely dispersed particles, bigger nitrides at ferrite grain boundaries develop exhibiting platelet-type morphology and possessing a crystal structure which can be also described as a superstructure derived from hexagonal δ-WN. Upon prolonged nitriding assumed discontinuous precipitation of the initially precipitated finely dispersed nitrides starts from the ferrite-grain boundaries resulting in lamellas consisting of alternate ferrite and hexagonal nitride lamellas, whereas the nitride lamellas having a Pitsch-Schrader orientation relationship with the surrounding ferrite matrix. The nitrides precipitated upon nitriding in the bulk were found to be unstable during H2 reduction at 470°C. Remarkably, upon such low temperature dissolution of the nitrides took place but only the nitrogen from the nitride particles could diffuse out of the nitride platelets and the specimen, leaving W-rich regions (W-clusters) at the location of the original precipitates.

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9

Peng, Jiayu, Juan José J. Giner Sanz, Livia Giordano, William P. Mounfield III, Graham Leverick, Yang Yu, Yuriy Román-Leshkov, and Yang Shao-Horn. "Design Principles for Transition Metal Nitride Stability and Ammonia Generation in Acid." ECS Meeting Abstracts MA2023-01, no. 39 (August 28, 2023): 2311. http://dx.doi.org/10.1149/ma2023-01392311mtgabs.

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Transition metal nitrides have shown great promise for reducing or eliminating the use of expensive precious-metal-based catalysts (e.g., Pt) in proton exchange membrane fuel cells and electrolyzers, but the use of these nitrides in such technologies is severely hindered by their dissolution at acidic pHs [1-2]. More importantly, the decomposition of transition metal nitrides in acid generates ammonia from the protonation of lattice nitrogen, giving rise to many false positives in previous reports of nitride catalysts for electrochemical nitrogen reduction to ammonia. For example, while nitrides such as VN [3], NbN [4], and Mo2N [5] have been computationally predicted to catalyze the reduction of nitrogen to ammonia, the experimentally observed ammonia has been attributed to the decomposition of nitrides in acid [6-8]. To tackle this challenge, motivated by our previous work [9-12] on the design principles of transition-metal-oxide-based catalysts, we established the stability descriptors of transition metal nitrides in acid. Such stability descriptors not only offer a fundamental understanding of nitride dissolution but also provide new guiding principles to optimize the intrinsic stability of nitrides for diverse acidic applications. In this work [13], combining ab initio calculations with synchrotron X-ray spectroscopies, we identified electronic-structure-based design principles governing the extent and kinetics of nitride dissolution and ammonia production in acid. We found that lowering the nitrogen 2p band center of transition metal nitrides with respect to the Fermi level leads to weakened metal-nitrogen bonds, increased labile metallic character, and a reduced barrier for the protonation of lattice nitrogen to produce ammonia, correlating with faster dissolution kinetics of nitrides in acid. Moreover, increasing the solubility of dissolved metal ions in acid was found to be critical in preventing surface oxide passivation to ensure the complete conversion from transition metal nitrides to ammonia. Based on these observations, a new mechanistic picture was formulated, where the initial protonation step of lattice nitrogen is critical to trigger nitride dissolution, and this proposed reaction scheme was supported by the pH-dependent dissolution kinetics of nitrides in acid. These design principles and mechanistic insights for producing ammonia and dissolving metal cations from the decomposition of nitrides in acid are essential for a variety of clean energy applications. For instance, such design principles can be leveraged to boost the stability of nitride catalysts for proton-exchange membrane fuel cells and electrochemical ammonia synthesis, where the dissolution of nitrides in acid has hindered their functions. Moreover, these descriptors for nitride dissolution and ammonia formation in acid provide emerging opportunities for designing novel nitride chemistries for distributed, on-demand ammonia generation. As nitrides represent an exciting, yet markedly unexplored chemical space, this work provides a blueprint to design multinary nitrides in such a vast materials space for various acidic applications, including electrocatalysis and beyond. References: [1] D. Göhl, et al. Nat. Mater. 19, 287 (2020). [2] M.E. Kreider, et al. ACS Appl. Mater. Interfaces 11, 26863 (2019). [3] Y. Abghoui, et al. ACS Catal. 6, 635 (2016). [4] Y. Abghoui and E. Skúlason, J. Phys. Chem. C 121, 6141 (2017). [5] I. Matanović, et al. Phys. Chem. Chem. Phys. 16, 3014 (2014). [6] B. Hu, et al. ACS Energy Lett. 4, 1053 (2019). [7] H.L. Du, et al. ACS Sustain. Chem. Eng. 7, 6839 (2019). [8] R. Manjunatha, et al. ChemCatChem 12, 438 (2020). [9] D.A. Kuznetsov†, J. Peng†, et al. J. Phys. Chem. C 124, 6562 (2020). († denotes equal contribution) [10] S. Yuan†, J. Peng†, B. Cai†, et al. Nat. Mater. 21, 673 (2022). († denotes equal contribution) [11] J. Peng, et al. Chem. Mater. 34, 7774 (2022). [12] J. Peng, et al. Nat. Rev. Mater. (2022) doi: 10.1038/s41578-022-00466-5. [13] J. Peng, et al. Joule (2022) accepted.

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Talley, Kevin R., Craig L. Perkins, David R. Diercks, Geoff L. Brennecka, and Andriy Zakutayev. "Synthesis of LaWN ₃ nitride perovskite with polar symmetry." Science 374, no. 6574 (December 17, 2021): 1488–91. http://dx.doi.org/10.1126/science.abm3466.

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Nitrides join the perovskite club Perovskite structured materials have a variety of uses as photovoltaics, capacitors, and micromechanical actuators, along with other applications. Oxides, halides, and chalcogenides all have large numbers of perovskite structured materials. Examples of perovskite nitrides are conspicuously absent, but Talley et al . managed to synthesize one (see the Perspective by Hong). Lanthanum tungsten nitride in the perovskite structure turns out to be piezoelectric, which is ideal for a variety of applications. Perovskite structured nitrides are very attractive because they could easily integrate with the large number of nitride-based semiconducting devices already in use. —BG

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Lüdtke, Tobias, Steven Orthmann, and Martin Lerch. "Bixbyite-type phases in the system Ta-Zr-O-N." Zeitschrift für Naturforschung B 72, no. 4 (April 1, 2017): 305–11. http://dx.doi.org/10.1515/znb-2017-0014.

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AbstractPhase-pure tantalum/zirconium oxide nitrides and nitrides were synthesized by the ammonolysis of amorphous oxide precursors. The nitrogen-rich oxide nitrides with variable anion composition and the nitride TaZrN3 crystallize in the cubic bixbyite-type structure (space group Ia3̅). The nitrogen content of these compounds has a significant influence on the cell parameters, the atomic positions, and the optical band gap. The results extend the already well-studied Ta–Zr–O–N system by new oxide nitrides in addition to the already known baddeleyite- and anosovite-type phases. TaZrN3 can be considered as a thermodynamically stable ternary variant of metastable Ta2N3.

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Mokrzycka, Magdalena, Adrianna Przybyło, Marek Góral, Barbara Kościelniak, Marcin Drajewicz, Tadeusz Kubaszek, Kamil Gancarczyk, et al. "The influence of plasma nitriding process conditions on the microstructure of coatings obtained on the substrate of selected tool steels." Advances in Mechanical and Materials Engineering 41 (2024): 5–16. http://dx.doi.org/10.7862/rm.2024.1.

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This study presents the results of research into the influence of the time of the plasma nitriding process on the microstructure of the coatings obtained. Cold-work tool steels (60WCrV8, 90MnCrV8, 145Cr6), hot-work tool steel (X37CrMoV5-1) and high-speed tool steel (HS6-5-2) were selected as substrate material. The processes were carried out under industrial conditions using an Ionit device from Oerlikon Metaplas with variable process times of 2, 4 and 6 hours. According to literature data, a nitriding mixture consisting of 5% nitrogen and 95% hydrogen was chosen, which allowed the expected diffusion layer to be obtained without a white layer (composed of iron nitrides). Analysis of elemental mapping indicates that the presence and content of nitride-forming elements influences the formation of alloy additive nitrides in the microstructure of the diffusion layer. It was also found that an increase in the duration of plasma nitriding, results in an increase in the depth of the nitrided layers formed on the substrate of high-alloy steels: X37CrMoV5-1 and HS6-5-2. Nitrides of alloying additives, present in the diffusion layer, are formed in the high-alloyed the hot-work steel X37CrMoV5-1, indicating that these steels are the most suitable for plasma nitriding of the entire tool steels analysed.

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Kondo, Naoki. "High Strength and High Toughness Anisotropic Silicon Nitrides Fabricated by Forging Technique." Key Engineering Materials 280-283 (February 2007): 1213–18. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.1213.

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Grain alignment control to make anisotropic microstructure is one of the most promising techniques to achieve superior mechanical properties in specific directions. Anisotropic silicon nitrides, which were fabricated by a forging technique, can show superior mechanical properties at room temperature as well as at elevated temperatures. A sinter-forged silicon nitride with yttria and alumina additives exhibited very high strength of 2.1GPa at room temperature, meanwhile that with lutetia additive showed high strength of 700MPa at 1500oC. Anisotropic silicon nitrides are also advantageous to achieve higher fracture energy. Such silicon nitrides can show 3~5 times higher fracture energy than isotropic ones. Sinter-forging technique is also applicable to fabricate porous anisotropic silicon nitrides. In this paper, fabrication and mechanical properties of anisotropic silicon nitrides are briefly described.

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Frenzel, Nancy, Torsten Otremba, Reinhard Schomäcker, Thorsten Ressler, and Martin Lerch. "Präparation und Charakterisierung von SiO2-geträgerten Zirconiumoxidnitriden mit hoher Oberfläche und Untersuchung ihrer katalytischen Aktivität bei der Ammoniakzersetzung / Synthesis, Characterization, and Catalytic Activity of Zirconium Oxide Nitrides Supported on High-surface SiO2." Zeitschrift für Naturforschung B 66, no. 2 (February 1, 2011): 147–54. http://dx.doi.org/10.1515/znb-2011-0207.

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Zirconium oxide nitrides are active ammonia decomposition catalysts for the production of hydrogen. We present a route to zirconium oxide nitrides with high surface area. The precursor used consisted of a high-surface-area silica material coated with zirconium alkoxide. Subsequent hydrolysis and calcination resulted in ZrO2 supported on SiO2. The high surface area of the material could be maintained in the following ammonolysis procedure leading to the corresponding zirconium oxide nitride. In contrast to the as-prepared ZrO2, the zirconium oxide nitrides exhibited a significant catalytic activity in ammonia decomposition, but compared to an iron oxide-based reference material, the new oxide nitrides showed a rather low activity. Nevertheless, zirconium oxide nitrides constitute suitable model systems for elucidating the effect of nitrogen in the anion substructure on the activity and selectivity of oxide-based ammonia decomposition catalysts.

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Holländer Pettersson, N., D. Lindell, F. Lindberg, and A. Borgenstam. "Formation of Chromium Nitride and Intragranular Austenite in a Super Duplex Stainless Steel." Metallurgical and Materials Transactions A 50, no. 12 (October 11, 2019): 5594–601. http://dx.doi.org/10.1007/s11661-019-05489-2.

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Abstract Precipitation of chromium nitrides and formation of intragranular austenite were studied in detail for the super duplex stainless steel grade 2507 (UNS S32750). The situation of multipass welding was simulated by heat treatment at 1623 K (1350 °C) and quenching followed by short heat treatments at 1173 K (900 °C). The microstructural evolution was characterized using transmission and scanning electron microscopy, electron backscatter, and transmission Kikuchi diffraction, and it was observed that the interior of the ferrite grains contained chromium nitrides after quenching. The nitrides were predominantly of CrN with a cubic halite-type structure and clusters of CrN-Cr2N where rod-shaped trigonal Cr2N particles had nucleated on plates of CrN. After heat treatment for 10 seconds at 1173 K (900 °C), the nitride morphology was transformed into predominantly rod-shaped Cr2N, and finely dispersed intragranular secondary austenite idiomorphs had formed in the nitride-containing areas within the ferrite grains. After 60 seconds of heat treatment, both the Cr2N nitrides and the secondary austenite were coarsened. Analysis of electron diffraction data revealed an inherited crystallographic relationship between the metastable CrN and the intragranular austenite. The mechanism of chromium nitride formation and its relation to secondary austenite formation in duplex stainless steels are discussed.

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Bauers, Sage R., Aaron Holder, Wenhao Sun, Celeste L. Melamed, Rachel Woods-Robinson, John Mangum, John Perkins, et al. "Ternary nitride semiconductors in the rocksalt crystal structure." Proceedings of the National Academy of Sciences 116, no. 30 (July 3, 2019): 14829–34. http://dx.doi.org/10.1073/pnas.1904926116.

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Inorganic nitrides with wurtzite crystal structures are well-known semiconductors used in optical and electronic devices. In contrast, rocksalt-structured nitrides are known for their superconducting and refractory properties. Breaking this dichotomy, here we report ternary nitride semiconductors with rocksalt crystal structures, remarkable electronic properties, and the general chemical formula MgxTM1−xN (TM = Ti, Zr, Hf, Nb). Our experiments show that these materials form over a broad metal composition range, and that Mg-rich compositions are nondegenerate semiconductors with visible-range optical absorption onsets (1.8 to 2.1 eV) and up to 100 cm2 V−1⋅s−1 electron mobility for MgZrN2 grown on MgO substrates. Complementary ab initio calculations reveal that these materials have disorder-tunable optical absorption, large dielectric constants, and electronic bandgaps that are relatively insensitive to disorder. These ternary MgxTM1−xN semiconductors are also structurally compatible both with binary TMN superconductors and main-group nitride semiconductors along certain crystallographic orientations. Overall, these results highlight MgxTM1−xN as a class of materials combining the semiconducting properties of main-group wurtzite nitrides and rocksalt structure of superconducting transition-metal nitrides.

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Park, Eun Young, Jae Hwan Pee, Yoo Jin Kim, and Woo Seok Cho. "Effects of Doping Elements on Residual Oxygen/Nitrogen Contents in Red Pigment of Tantalum Nitrides (Ta₃N₅)." Materials Science Forum 654-656 (June 2010): 2386–89. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.2386.

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Tantalum nitride (Ta3N5) is a nontoxic red pigment that is being developed as a substitute for Cd-related pigments Ta3N5 is produced by the nitridation and heat treatment of amorphous Tantalum precursors. Doping elements were added in the precursor manufacturing stage to improve the red color tone of tantalum nitride. Grain growth was observed in nitrides that formed second phases, such growth led to an increase in the average grain size comprared to undoped nitrides, and the colors declined as the oxygen content increased. Nitrides that did not form second phases in response to doping elements remained a single-phase Ta3N5 and exhibited an excellent red color with a high nitrogen content. We determined that a change in the oxygen/nitrogen contents affected the color manifestation, which depended on the amount by which doping was increased.

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Zhao, Zhao Hui, Han Bo Zou, and Wei Ming Lin. "Influence of Final Nitriding Temperature on the Preparation and the Catalytic Performance of CoMoN_x/CNTs for Ammonia Decomposition." Advanced Materials Research 557-559 (July 2012): 1514–17. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.1514.

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A series of cobalt-molybdenum nitride catalysts were prepared using Co-Mo oxide precursors via temperature-programmed reaction in N2-H2 mixed gases. The catalysts were characterized by N2 physical adsorption, X-ray diffraction, temperature-programmed desorption of H2. Their catalytic performance was evaluated in the model reaction of ammonia decomposition. The influence of the final nitriding temperatures on the surface properties and the catalytic perfomance of CoMoNx/CNTs were described. The catalyst nitrided at 650°C shows the best catalytic performance. The results indicated that a suitable final nitriding temperature contributes directly to the formation of nitrides and favor the catalyst activity.

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Zheng, Fangfang, Xu Xiao, Juan Xie, Liujiang Zhou, Youyong Li, and Huilong Dong. "Structures, properties and applications of two-dimensional metal nitrides: from nitride MXene to other metal nitrides." 2D Materials 9, no. 2 (February 24, 2022): 022001. http://dx.doi.org/10.1088/2053-1583/ac52b3.

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Abstract The two-dimensional (2D) metal nitrides (MNs), including group IIA nitrides, group IIIA nitrides, nitride MXene and other transition metal nitrides (TMNs), exhibit unique electronic and magnetic characteristics. The 2D MNs have been widely studied by experimental and computational approaches and some of them have been synthesized. Herein we systematically reviewed the structural, electronic, thermal, mechanical, magnetic and optical properties of the 2D MNs that have been reported in recent years. Based on their unique properties, the related applications of 2D MNs on fields like electronics, spintronics, sensing, catalysis, and energy storage were discussed. Additionally, the lattice structures and synthetic routes were also summarized as supplements of the research progress of 2D MNs family. Furthermore, we provided insights into the research prospects and future efforts that need to be made on 2D MNs.

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Vaidhyanathan, B., D. K. Agrawal, and R. Roy. "Novel Synthesis of Nitride Powders by Microwave-assisted Combustion." Journal of Materials Research 15, no. 4 (April 2000): 974–81. http://dx.doi.org/10.1557/jmr.2000.0139.

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A novel and simple microwave-assisted combustion procedure for the synthesis of a number of technologically important metal nitrides was demonstrated. The method involves the combustion reaction of a porous metal powder compact with N2 gas in the microwave field and provides phase-pure metal nitride products (consisting of fine particles, fibers, and whiskers) within minutes. The ignition and combustion temperatures of the reaction were found to vary as a function of compaction pressure. The microwave-prepared nitrides were characterized using x-ray diffraction, scanning electron microscopy energy dispersive spectroscopy, thermogravimetric analysis, and infrared spectroscopy. The present microwave-assisted hybrid-heating procedure allows the preparation of nitrides with good crystallinity, structural uniformity, and phase purity, and appears to have general applicability for the preparation of metal nitrides (using the respective metals or even their oxides).

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Zhikharev, V. M., and M. S. Pavlovskaya. "The Dependence of Gibbs Energy of Formation of Niobium Mononitride on its Composition and Temperature in the Range of 1773-2023 K." Solid State Phenomena 284 (October 2018): 139–45. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.139.

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The article demonstrates the applicability of the interaction parameter method for describing the thermodynamic properties of non-stoichiometric niobium nitrides at temperatures of 1773 ± 2023 K. The authors obtained the equation of dependence of the nitride dissociation elasticity on its composition and temperature. They derived the expression for calculating Gibbs energy of formation of nitrides with a set composition, including stoichiometric, in the range of 1773 - 2023 K.

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22

Chandrasekhar, D., D. J. Smith, S. Strite, M. E. Lin, and H. Morkoc. "Characterization of group Ill-nitrides by high-resolution electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 846–47. http://dx.doi.org/10.1017/s0424820100171961.

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The Group III-nitride semiconductors A1N, GaN, and InN are of interest for their potential applications in short wavelength optoelectronic devices. This interest stems from their direct wideband gapswhich range from 1.9 eV (InN), to 3.4 eV (GaN), to 6.2 eV (A1N). If high quality nitride films can besuccessfully grown, then optoelectronic devices with wavelengths ranging from the visible to the deepultraviolet region of the electromagnetic spectrum are theoretically possible. Recently, LED's basedon GaN and InGaN QW's were demonstrated. Also, their excellent thermal properties make them ideal candidates for high-temperature and high-power devices. Many problems plague nitride research, especiallythe lack of suitable substrate materials that are both lattice- and thermal-matched to the nitrides. The crystal structure of these materials is strongly influenced by the substrate and its orientation.For example, although the equilibrium crystal structure of these nitrides is wurtzite, zincblende phase can be nucleated under nonequilibrium growth conditions but only on cubic substrates. These zincblende nitrides represent new material systems with properties that differ from their wurtzite counterparts. Recently, good quality material has been produced employing metalorganic vapor phase epitaxy (MOVPE) and reactive molecular beam epitaxy (RMBE) techniques with incorporation of buffer layers.

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Wang, Liangbiao, Yanxia Pan, Qianli Shen, Junhao Zhang, Keyan Bao, Zhengsong Lou, Dejian Zhao, and Quanfa Zhou. "Sulfur-assisted synthesis of indium nitride nanoplates from indium oxide." RSC Advances 6, no. 100 (2016): 98153–56. http://dx.doi.org/10.1039/c6ra22471g.

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Ye, Chao, and Qing Peng. "Mechanical Stabilities and Properties of Graphene-like 2D III-Nitrides: A Review." Crystals 13, no. 1 (December 22, 2022): 12. http://dx.doi.org/10.3390/cryst13010012.

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Mechanical stabilities and properties are critical in real applications of materials, as well as material and machine design. With the success of graphene, graphene-like materials arose tremendous interest in the past few years. Different from bulk materials, two-dimensional (2D) materials have prominent non-linear elastic behaviors. Here, we briefly review the mechanical stabilities and properties of graphene-like 2D III-nitrides, including boron nitride (BN), aluminum nitride (AlN), gallium nitride (GaN), indium nitride (InN), and thallium nitride (TlN). These nitrides are excellent wide band gap semiconductors very suitable for modern electronic and optoelectronic applications. As a result, they play a central role in solid-state light-emitting devices. Their Young’s modulus, Poisson’s ratio, ultimate tensile strength, and elastic limits under various strains are extensively studied, as well as their high-order elastic constants and non-linear behaviors. These studies provide a guide for their practical applications and designs.

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Rounaghi, Seyyed Amin, Danny E. P. Vanpoucke, Hossein Eshghi, Sergio Scudino, Elaheh Esmaeili, Steffen Oswald, and Jürgen Eckert. "Mechanochemical synthesis of nanostructured metal nitrides, carbonitrides and carbon nitride: a combined theoretical and experimental study." Physical Chemistry Chemical Physics 19, no. 19 (2017): 12414–24. http://dx.doi.org/10.1039/c7cp00998d.

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26

Navarro-Quezada, Andrea. "Magnetic Nanostructures Embedded in III-Nitrides: Assembly and Performance." Crystals 10, no. 5 (May 1, 2020): 359. http://dx.doi.org/10.3390/cryst10050359.

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III-Nitride semiconductors are the materials of choice for state-of-the-art opto-electronic and high-power electronic applications. Through the incorporation of magnetic ions, like transition metals and rare-earths, III-Nitrides have further extended their applicability to spintronic devices. However, in most III-Nitrides the low solubility of the magnetic ions leads to the formation of secondary phases that are often responsible for the observed magnetic behavior of the layers. The present review summarizes the research dedicated to the understanding of the basic properties, from the fabrication to the performance, of III-Nitride-based phase-separated magnetic systems containing embedded magnetic nanostructures as suitable candidates for spintronics applications.

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27

Li, Shihang, and Lei Kang. "Nitride Wide-Bandgap Semiconductors for UV Nonlinear Optics." Crystals 13, no. 11 (October 26, 2023): 1536. http://dx.doi.org/10.3390/cryst13111536.

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Nitride wide-bandgap semiconductors possess a wide tunable energy bandgap and abundant coordination anionic groups. This suggests their potential to display nonlinear optical (NLO) properties in the UV wavelength spectrum. This paper reports recent progress and material discoveries in exploring UV NLO structures using nitrides. The study emphasizes their underlying structure–property correlations in order to provide a summary of the potential performance and application value of important nitride NLO crystals. Additionally, the text underscores the benefits of nitrides in terms of optical transparency, second-harmonic-generation effects, and the birefringent phase matching the output wavelength limits, while addressing current issues in terms of theoretical outlook and experimental exploration.

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Kerdoud, Djahida, Faouzia Benkafada, Nora Boussouf, and Chahrazed Benhamideche. "Nitride Materials: Synthesis, Crystal Structures, and Optical Properties." Annales de Chimie - Science des Matériaux 46, no. 2 (April 30, 2022): 103–8. http://dx.doi.org/10.18280/acsm.460206.

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Our research involves the preparation of transition metal nitrides of the composition Mn4N, NbN, Mo2N, TaN and ZrN. The synthesis of Li3N binary alkali metal nitride was also part of this work. Simple and cost-effective methods with relatively low impact on the environment have been privileged in the selection. The experimental work has focused on determining the optimum conditions of synthesis and the convenient high yield route to the desired nitrides, and ultimately improvement of the properties of the final materials. All samples were characterised by X-ray powder diffraction. Their structures will be discussed in more detail here. Optical band gap has been calculated from diffuse reflectance measurements. The air sensitivity of the nitrides was also probed.

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Morishita, Takuya, Hirotaka Okamoto, Yoshihide Katagiri, Mitsumasa Matsushita, and Kenzo Fukumori. "A high-yield ionic liquid-promoted synthesis of boron nitride nanosheets by direct exfoliation." Chemical Communications 51, no. 60 (2015): 12068–71. http://dx.doi.org/10.1039/c5cc04077a.

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Li, Xiaoying, Wenbo Dou, Linhai Tian, and Hanshan Dong. "Combating the Tribo-Corrosion of LDX2404 Lean Duplex Stainless Steel by Low Temperature Plasma Nitriding." Lubricants 6, no. 4 (October 19, 2018): 93. http://dx.doi.org/10.3390/lubricants6040093.

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A lean duplex stainless steel, LDX2404, was DC plasma nitrided under a range of treatment conditions. The microstructure characterisation evaluation of the treated samples revealed that a dense, super-hard surface layer can be produced by low-temperature (<450 °C) plasma treatments. The original austenite phase became S-phase and the ferrite phase was supersaturated with nitrogen and ε-Fe3N nitride precipitated from it. When plasma nitriding was carried out at above 450 °C, chromium nitrides precipitated in the surface nitrided layer. Compared to the untreated samples, the surface hardness of the lean duplex stainless steel (DSS) is increased up to four times. The dry wear resistance increased when increasing the treatment temperature. In contrast, the low-temperature treated samples showed the best performance in the electrochemical corrosion and corrosion-wear tests; the performance of the high temperature (>450 °C) plasma nitrided samples was found to be significantly worse than that of the untreated material.

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Amudhavalli, A., M. Manikandan, A. Jemmy Cinthia, R. Rajeswarapalanichamy, and K. Iyakutti. "Structural, Electronic, and Mechanical Properties of CoN and NiN: An Ab Initio Study." Zeitschrift für Naturforschung A 72, no. 4 (April 1, 2017): 321–30. http://dx.doi.org/10.1515/zna-2016-0377.

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AbstractThe structural stabilities of cobalt mononitride (CoN) and nickel mono-nitride (NiN) were investigated among the crystal structures, namely, NaCl (B1), CsCl (B2), and zinc blende (B3). It was found that the zinc blende (B3) phase was the most stable phase for both nitrides. A pressure-induced structural phase transition from B3 to B1 phase was predicted in these nitrides. The computed lattice parameter values were in agreement with the experimental values and other theoretical values. The electronic structures reveal that these nitrides are metallic at zero pressure. The computed elastic constants indicate that CoN and NiN are mechanically stable in the B1 and B3 phases. The variations of the elastic constants, bulk modulus, shear modulus, Poisson’s ratio, and elastic anisotropy factor with pressure were investigated. The Debye temperature θD values are reported for both the nitrides in their B1 and B3 phases. The high-pressure NaCl phase of both CoN and NiN were found to be ferromagnetic.

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Kikkawa, Shinichi, K. Sakon, Y. Kawaai, and T. Takeda. "Magnetoresistance of Post-Annealed Iron Nitride Related Thin Films." Advances in Science and Technology 52 (October 2006): 70–74. http://dx.doi.org/10.4028/www.scientific.net/ast.52.70.

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Iron nitrides thermally decompose to α-Fe releasing their nitrogen above 300°C. MR effect was found out in the thin films obtained by post-annealing of the following two kinds of sputter deposited iron nitride related films. (1) α-Fe particles dispersed in AlN granular film was obtained by an annealing of Al0.31Fe0.69N sputter deposited film in hydrogen. The MR=0.82% was found out in this nitride system. (2) Fe3O4 thin films were prepared by thermal decomposition of sputter deposited iron nitride films in low oxygen partial pressure. The iron nitrides were defect rock salt type γ΄˝-FeNx (0.5≤x≤0.7) and zinc blende type γ˝-FeNy (0.8≤y≤0.9) at the sputter nitrogen gas pressure of 1Pa and 6Pa. MR ratios of the oxide films were about 2%.

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33

Fedorov, Maxim S., Nikolay A. Baydakov, Alexander N. Zhiganov, and Dmitry V. Zozulya. "ANALYSIS OF EXISTING METHODS FOR URANIUM-PLUTONIUM MIXED NITRIDE FUEL FAB-RICATION IN RUSSIA AND ABROAD." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no. 6 (May 12, 2020): 12–18. http://dx.doi.org/10.6060/ivkkt.20206306.6185.

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This paper presents a review and a brief analysis of existing methods for producing mixed uranium nitride and plutonium, developed by both Russian and foreign scientists. The main parameters of the processes are considered, and their advantages and disadvantages are studied. Currently, the main areas of nitride fuel production are the metal hydride method and carbothermic reduction from the starting oxides. The methods are traditional ceramic technology. The starting products for the manufacture of nitride fuel powder can be either oxides (uranium dioxide and plutonium dioxide) or metals (uranium, plutonium and their alloys). To date, the technology for the manufacture of nitride fuel powder has not been finally selected. When considering existing methods, significant emphasis was placed on industrial applications and the simplicity of the hardware design processes. The laboratory methods are reflected in the work, which make it possible to simplify the process and reduce the costs of obtaining powders of mixed uranium and plutonium nitrides. However, they have significant difficulties in the technological implementation and low productivity of the processes. Of special interest among laboratory methods for producing mixed uranium and plutonium nitrides is the method of high-voltage electric pulse consolidation. This method allows sintering of tablets at the stage of powder pressing from mixed uranium and plutonium nitrides by passing a short high-voltage discharge with a power of several kW directly through the powder.

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Shi, Zhiming, Hang Zang, Xiaobao Ma, Yuxin Yang, Ke Jiang, Yang Chen, Yuping Jia, Xiaojuan Sun, and Dabing Li. "Grain boundary-driven magnetism in aluminum nitride." Applied Physics Letters 121, no. 24 (December 12, 2022): 242102. http://dx.doi.org/10.1063/5.0132005.

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Introducing magnetism into III-nitrides to achieve diluted magnetic semiconductors (DMSs) is promising to broaden the applications of III-nitrides. The most popular technique is doping transition metals; however, these structural imperfections are unstable due to significant lattice incompatibility with the host. As a result, the fabrication of high-quality samples is quite difficult through the current growth techniques. Therefore, realizing intrinsic and robust magnetism in III-nitrides is quite desirable. Here, we adapted aluminum nitride as the example to theoretically predict the stable magnetism driven by the ubiquitous grain boundaries (GBs). The magnetism strongly depends on GBs tilt angles. These GBs cores contain homo-elemental bonds antiferromagnetically coupled at high tilt angles (>16.7°) due to the short coupling distances. The Tc was as high as 293 K at the tilt angle of 32.2°. Importantly, the magnetism induced by GBs is robust regarding carrier doping and strain, implying stable magnetism under working conditions. Our results provided a feasible and flexible approach to convert III-nitride into a wide-gap DMS by engineering the topological GBs.

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L, Isaeva, Lev I, Kamkin V, and Projdak Yu. "Raspredelenie azota, titana i alyuminiya mezhdu nitridami i tverdym rastvorom v stalyah tipa ATYu." Theory and practice of metallurgy, no. 6 (September 22, 2019): 31–35. http://dx.doi.org/10.34185/tpm.5.2019.03.

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Quantitative data on the distribution of nitrogen, titanium and aluminum between nitrides and solid solution have been established in ATU steels. The optimal amount of titanium in 20ATU steel was determined, which leads to the best interfacial distribution of nitride-forming elements (N, Al, Ti) under hot rolling conditions. For the most complete binding of nitrogen to AlN nitrides, the amount of aluminum in 20ATU steel should be ≥40 10-3 wt. %. To obtain fine nitrides and maintain a sufficiently high fluidity of steel 20ATU optimal content of aluminum should be (40-60) 10-3 wt. %. It is recommended to subject ATU type steels to heat treatment at optimal temperature and time Keywords: Carbon, low-alloy steels, nitrogen, titanium, aluminum, interfacial distribution

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36

Danielsen, Hilmar Kjartansson. "Atomic Resolution Microscopy of Nitrides in Steel." Materials Science Forum 783-786 (May 2014): 1617–22. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.1617.

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MN and CrMN type nitride precipitates in 12%Cr steels have been investigated using atomic resolution microscopy. The MN type nitrides were observed to transform into CrMN both by composition and crystallography as Cr diffuses from the matrix into the MN precipitates. Thus a change from one precipitate type to another does not necessarily involve nucleation of the new precipitate type followed by dissolution of the old precipitates. By studying the interface between these nitrides and the matrix, it could be observed that the MN and CrMN type precipitates had a few nanometers thick amorphous layer between the crystalline nitride and ferrite matrix. Usually precipitates are described as having (semi) coherent or incoherent interfaces, but in this case it is more energetically favourable to create an amorphous layer instead of the incoherent interface.

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37

Bauer, Christoph, Aberra Mogessie, and Ulrike Galovsky. "Formation, stability, and presence of magnesium nitride in magnesium recycling processes." International Journal of Materials Research 97, no. 2 (February 1, 2006): 164–68. http://dx.doi.org/10.1515/ijmr-2006-0029.

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Abstract In this study an attempt has been made to identify analytical methods for detecting magnesium nitride, and document in which part of the magnesium recycling process this phase is concentrated. The samples were taken from a continuous fluxfree recycling session, where an AZ91D magnesium alloy was remelted and purified by blowing nitrogen through the melt. Exothermic reactions took place when magnesium nitride reacted to ammonia and Brucite and also when aluminium nitride reacted to ammonia and Gibbsite in a moisture-bearing environment. Because of this, it was essential to avoid any contact with moisture during the whole sampling and preparation process. The samples were exclusively handled in an argon atmosphere. Due to their crystallinity and Raman activity the nitrides were detected with X-ray diffraction and Raman spectroscopy, respectively. With the scanning electron microscope it was difficult to analyze small concentrations of nitrides since large, stable crystals were absent and the carbon coating absorbs the nitrogen Kα line. The Mg-alloy was found to be free of impurities. Although nitrides were expected to be concentrated in the slag because of their greater density, they were found adhering at the nitrogen bubbles and accumulating in the dross. Large amounts of oxides were concentrated in the slag.

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38

Vinu, Ajayan, Srinivasan Anandan, Narasimhan Gokularkrishnan, Pavuluri Srinivasu, Toshiyuki Mori, and Katsuhiko Ariga. "Mesoporous Nitrides through Nano-Hard Templating Techniques." Solid State Phenomena 119 (January 2007): 291–94. http://dx.doi.org/10.4028/www.scientific.net/ssp.119.291.

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Mesoporous carbon nitride materials have been synthesized using SBA-15 by pore filling technique whereas mesoporous boron nitride and boron carbon nitride have been prepared by elemental substitution technique using mesoporous carbon as template. The obtained materials have been unambiguously characterized by sophisticated techniques such as XRD, HRTEM, EELS, XPS, FT-IR and N2 adsorption. The textural parameters of the materials are quite higher as compared to the respective nonporous nitrides. These materials could offer great potential for the applications, such as catalytic supports, gas storage, biomolecule adsorption and drug delivery.

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Keddam, Mourad, R. Kouba, Redoune Chegroune, and B. Bouarour. "Surface Characterization of a Nitrided Low Alloy Steel." Defect and Diffusion Forum 312-315 (April 2011): 70–75. http://dx.doi.org/10.4028/www.scientific.net/ddf.312-315.70.

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The 32CrMoV13 low alloy steel was gas nitrided at 550°C, for three time durations (6.5, 13 and 20 h) and under a variable nitriding potential (1, 2.2 and 6 atm-0.5). The generated nitride layers were characterized by SEM observations, XRD and GDOS analyses as well as microhardness testing. The XRD analysis indicates that the compound layer was composed of and iron nitrides and CrN phase. The surface hardness (inside the compound layer) was found to be dependent on the nitriding potential value, its value increases as rises. It was shown by GDOS analysis that the upper and lower nitrogen concentrations at the (compound layer / diffusion zone) interface are approximatively: 4 and 0.88 wt. % N, respectively.

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Grant, Lauren N., Balazs Pinter, Takashi Kurogi, Maria E. Carroll, Gang Wu, Brian C. Manor, Patrick J. Carroll, and Daniel J. Mindiola. "Molecular titanium nitrides: nucleophiles unleashed." Chemical Science 8, no. 2 (2017): 1209–24. http://dx.doi.org/10.1039/c6sc03422e.

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Reactivity studies of a rare example of a molecular titanium nitride are presented. A combination of theory and NMR spectroscopy provide a description of the bonding in the these nitrides, the role of the counter cation, K⁺, as well as the origin of their highly downfield ¹⁵N NMR spectroscopic shifts.

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Ratajski, Jerzy, and Roman Olik. "Development of Nitrided Layer during Nitriding of Steel." Advanced Materials Research 83-86 (December 2009): 1025–34. http://dx.doi.org/10.4028/www.scientific.net/amr.83-86.1025.

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The present work is devoted to research the influence of micro-structural evolution of the compound zone (iron (carbo)nitrides zone) upon development of hardness profiles in diffusion zone. A different phase structure of iron (carbo)nitrides zone on steel as compared to iron, further changing with the process, may result in upsetting the quasi-equilibrium of nitrogen concentration in the iron (carbo)nitrides zone/diffusion zone interface and may as a result have impact on the kinetics of this layer’s growth. Aimed at solving this problem there was a research carried out to evaluate influence of (carbo)nitrides zone, with intentionally created diametrically different phase composition, on hardness profiles in the diffusion zone. Based on the research conducted, it was shown that the evolution of phase structure of the compound zone contributes significantly, regardless of nitrogen potential and temperature, to the formation of the diffusion zone and in particular to its effective thickness. It makes this complex picture of nitrided case development on steel even more intricated.

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42

Eom, J. Y., V. Shankar Rao, H. S. Kwon, K. S. Nam, and S. C. Kwon. "Experiments and modeling study on growth behavior of Cr-nitrides formed on electroplated hard Cr during ion-nitriding." Journal of Materials Research 18, no. 4 (April 2003): 861–67. http://dx.doi.org/10.1557/jmr.2003.0118.

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The structure and composition of Cr-nitrides formed on an electroplated hard Cr layer during an ion-nitriding process were analyzed, and its growth kinetics was examined as a function of the ion-nitriding temperature and time to establish a computer simulation model for the prediction of growth behavior of the Cr-nitride layer. The Cr-nitrides formed during the ion-nitriding at 550–770 °C were composed of outer CrN and inner Cr2N layers. A nitrogen diffusion model in the multilayer, based on fixed-grid finite difference method, was applied to simulate the growth kinetics of Cr-nitride layers. By measuring the thickness of Cr-nitride layers as a function of ion-nitriding temperature and time, the activation energy (Q) and nitrogen diffusion constant (Do) were determined for growth of CrN and Cr2N; the result was applied to simulate the growth kinetics of Cr-nitride layers, and reasonable good agreement was obtained with the experimental results.

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Mudiyanselage, Dinusha Herath, Dawei Wang, Yuji Zhao, and Houqiang Fu. "Intersubband transitions in nonpolar and semipolar III-nitrides: Materials, devices, and applications." Journal of Applied Physics 131, no. 21 (June 7, 2022): 210901. http://dx.doi.org/10.1063/5.0088021.

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In the last two decades, the third-generation wide bandgap semiconductor III-nitrides have revolutionized a myriad of electronic and photonic devices and applications, including power electronics, extreme-environment electronics, RF amplifiers, and optoelectronics such as light-emitting diodes and laser diodes. Recently, III-nitride heterostructures (e.g., AlGaN/GaN) based intersubband transition (ISBT) has garnered considerable research interest for infrared (IR), terahertz (THz), and ultrafast optoelectronics (e.g., photodetectors and quantum cascade lasers) due to its large conduction band offset, large optical phonon energy, and promising room-temperature operation. This paper presents a comprehensive review on the recent progress and challenges of III-nitrides based ISBT from the perspectives of materials, structures, devices, and applications, with a focus on nonpolar and semipolar III-nitrides. Various device structures have been demonstrated for III-nitrides based ISBT, including quantum wells, dots, and wires, among which AlGaN/GaN quantum wells are the most widely used. The effects of device parameters, crystal orientations, and doping on the ISBT properties of AlGaN/GaN quantum wells are discussed. Although the room-temperature operation is still elusive, theoretical and experimental studies show that nonpolar and semipolar III-nitrides based ISBT exhibits tunable ISBT wavelength from far-IR to THz spectral range with higher efficiency compared with polar c-plane ISBT. This review can serve as a gateway to and an important reference for the recent progress and challenges of III-nitrides based ISBT and its potential applications in sensing, communication, ultrafast optoelectronics, and integrated photonics.

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Wu, Kefeng, Siyu Huang, Wenliang Wang, and Guoqiang Li. "Recent progress in III-nitride nanosheets: properties, materials and applications." Semiconductor Science and Technology 36, no. 12 (October 27, 2021): 123002. http://dx.doi.org/10.1088/1361-6641/ac2c26.

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Abstract As compared with their bulk materials, III-nitride nanosheets, including gallium nitride, aluminium nitride, indium nitride, reveal wider bandgap, enhanced optical properties, anomalously temperature-dependent thermal conductivity, etc, which are more suitable for the fabrication of nano-photodetectors, nano-field electron transistors, etc, for the application in the fields of nano-optoelectronics and nano-electronics. Although the properties of III-nitrides have been predicted based on the first-principles calculation, the experimental realization of III-nitride nanosheets has been restricted primarily due to dangling bonds on the surface and strong built-in electrostatic field caused by wurtzite/zinc-blende structures. To tackle these issues, several effective approaches have been introduced, and the distinct progress has been achieved during the past decade. In this review, the simulation and prediction of properties of III-nitride nanosheets are outlined, and the corresponding solutions and novel developed techniques for realisation of III-nitride nanosheets and defect control are discussed in depth. Furthermore, the corresponding devices based on the as-grown III-nitride nanosheets are introduced accordingly. Moreover, perspectives toward the further development of III-nitrides nanosheets and devices are also discussed.

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45

Wostatek, Thomas, V. Y. M. Rajesh Chirala, Nathan Stoddard, Ege N. Civas, Siddha Pimputkar, and Saskia Schimmel. "Ammonothermal Crystal Growth of Functional Nitrides for Semiconductor Devices: Status and Potential." Materials 17, no. 13 (June 25, 2024): 3104. http://dx.doi.org/10.3390/ma17133104.

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The state-of-the-art ammonothermal method for the growth of nitrides is reviewed here, with an emphasis on binary and ternary nitrides beyond GaN. A wide range of relevant aspects are covered, from fundamental autoclave technology, to reactivity and solubility of elements, to synthesized crystalline nitride materials and their properties. Initially, the potential of emerging and novel nitrides is discussed, motivating their synthesis in single crystal form. This is followed by a summary of our current understanding of the reactivity/solubility of species and the state-of-the-art single crystal synthesis for GaN, AlN, AlGaN, BN, InN, and, more generally, ternary and higher order nitrides. Investigation of the synthesized materials is presented, with a focus on point defects (impurities, native defects including hydrogenated vacancies) based on GaN and potential pathways for their mitigation or circumvention for achieving a wide range of controllable functional and structural material properties. Lastly, recent developments in autoclave technology are reviewed, based on GaN, with a focus on advances in development of in situ technologies, including in situ temperature measurements, optical absorption via UV/Vis spectroscopy, imaging of the solution and crystals via optical (visible, X-ray), along with use of X-ray computed tomography and diffraction. While time intensive to develop, these technologies are now capable of offering unprecedented insight into the autoclave and, hence, facilitating the rapid exploration of novel nitride synthesis using the ammonothermal method.

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Wang, Pei, Shanmin Wang, Yongtao Zou, Jinlong Zhu, Duanwei He, Liping Wang, and Yusheng Zhao. "Novel Nitride Materials Synthesized at High Pressure." Crystals 11, no. 6 (May 29, 2021): 614. http://dx.doi.org/10.3390/cryst11060614.

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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 ferr ous 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 ion-exchange 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.

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Chen, Long, Tamás I. Korányi, and Emiel J. M. Hensen. "Transition metal (Ti, Mo, Nb, W) nitride catalysts for lignin depolymerisation." Chemical Communications 52, no. 60 (2016): 9375–78. http://dx.doi.org/10.1039/c6cc04702e.

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Greenaway, Ann L., Celeste L. Melamed, M. Brooks Tellekamp, Rachel Woods-Robinson, Eric S. Toberer, James R. Neilson, and Adele C. Tamboli. "Ternary Nitride Materials: Fundamentals and Emerging Device Applications." Annual Review of Materials Research 51, no. 1 (July 26, 2021): 591–618. http://dx.doi.org/10.1146/annurev-matsci-080819-012444.

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Interest in inorganic ternary nitride materials has grown rapidly over the past few decades, as their diverse chemistries and structures make them appealing for a variety of applications. Due to synthetic challenges posed by the stability of N2, the number of predicted nitride compounds dwarfs the number that has been synthesized, offering a breadth of opportunity for exploration. This review summarizes the fundamental properties and structural chemistry of ternary nitrides, leveraging metastability and the impact of nitrogen chemical potential. A discussion of prevalent defects, both detrimental and beneficial, is followed by a survey of synthesis techniques and their interplay with metastability. Throughout the review, we highlight applications (such as solid-state lighting, electrochemical energy storage, and electronic devices) in which ternary nitrides show particular promise.

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Kikkawa, Shinichi. "Nanocrystals of Nitrides and Oxides." Journal of Nano Research 24 (September 2013): 16–25. http://dx.doi.org/10.4028/www.scientific.net/jnanor.24.16.

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Nanocrystals are important to attain high performance in optical & magnetic materials such as phosphors, laser emitters and information recording media. They are also required in future devices that involve magnetoresistance, logic gates, magnetic resonance and metamaterials. Nanocrystals of oxides and nitrides (and oxynitrides) were studied as nanosized powders, nanowires and dispersed granular thin films. Recent advancements of such nanocrystals prepared at Hokkaido University are introduced in this paper. Nanocrystals were prepared in transparent conducting oxides, white LED phosphor oxides and oxynitrides and magnetic iron nitride. Nanowires were grown in semiconducting gallium oxynitride and magnetic nanogranular thin films were prepared both in oxide and nitride.

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Liu, Suyan, Quan Huo, Rongna Chen, Peipei Chen, Yuan Li, and Yang Han. "Synthesis and Characterization of an Iron Nitride Constructed by a Novel Template of Metal Organic Framework." Journal of Spectroscopy 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/362103.

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An iron nitride with high surface area was synthesized from an iron-based metal organic framework (Fe-MOF) in this work. During the synthesis process, the Fe-MOF of MIL-53 served as a hard template, a template to impart a certain degree of morphology for iron oxide products and to form porosities for iron nitride products. Moreover, it played the roles of iron sources for the synthesis of the final iron oxides and the iron nitrides. The physicochemical properties of the materials were characterized by a series of technologies including XRD, SEM, and N2-adsorption/desorption. The results showed that the iron nitride synthesized from MIL-53 wasα-Fe2-3N. And, theα-Fe2-3N showed the morphology with loosely aggregated particles which favored the formation of rich interparticle porosities. As a result, the surface area of theα-Fe2-3N was larger than those of samples usingα-Fe2O3as precursors and its value was 41 m2/g. In addition, the results agreed that both raw material properties (such as crystallinity and surface areas) and nitriding approaches had significant effects on the surface areas of iron nitrides. Also the results were proved by the iron oxide synthesized with different methods. This new synthetic strategy could be a general approach for the preparation of late transition metal nitrides with peculiar properties.

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Journal articles on the topic 'Nitrides'

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