Artículos de revistas: "Molybdenum carbides"

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De Bonis, Angela, Mariangela Curcio, Antonio Santagata, Agostino Galasso y Roberto Teghil. "Transition Metal Carbide Core/Shell Nanoparticles by Ultra-Short Laser Ablation in Liquid". Nanomaterials 10, n.º 1 (14 de enero de 2020): 145. http://dx.doi.org/10.3390/nano10010145.

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Transition metal carbide nanoparticles are a class of technological interesting materials with a wide range of applications. Among metal carbides, tantalum carbides have good compatibility with the biological environment while molybdenum carbides are used as catalyst in electrochemical reactions. Laser ablation of bulk transition metal targets in some liquids is here reported and laser ablation in organic solvents is used as simple synthetic strategy for the production of carbide nanostructures. Herein, the nanoparticles produced by ultra-short laser ablation of tantalum and molybdenum in water, acetone, ethanol and toluene have been characterized by TEM, XRD and XPS analysis. The combined effect of metal and solvent chemical and physical properties on the composition of the nanomaterials obtained has been pointed out. In particular, the different reactivity of Ta and Mo with respect to oxidizing species determines the composition of particles obtained in water, on the other hand the organic solvents decomposition allows to obtain transition metal carbide (TMC) nanoparticles. The observed carbonaceous shell formed on TMC allows to protect the particle’s carbidic core and to improve and tailor the applications of these nanomaterials.

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Gavrilova, Natalia, Maria Myachina, Victor Nazarov y Valery Skudin. "Simple Synthesis of Molybdenum Carbides from Molybdenum Blue Nanoparticles". Nanomaterials 11, n.º 4 (30 de marzo de 2021): 873. http://dx.doi.org/10.3390/nano11040873.

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In recent years, much attention has been paid to the development of a new flexible and variable method for molybdenum carbide (Mo2C) synthesis. This work reports the applicability of nano-size clusters of molybdenum blue to molybdenum carbide production by thermal treatment of molybdenum blue xerogels in an inert atmosphere. The method developed made it possible to vary the type (glucose, hydroquinone) and content of the organic reducing agent (molar ratio R/Mo). The effect of these parameters on the phase composition and specific surface area of molybdenum carbides and their catalytic activity was investigated. TEM, UV–VIS spectroscopy, DTA, SEM, XRD, and nitrogen adsorption were performed to characterize nanoparticles and molybdenum carbide. The results showed that, depending on the synthesis conditions, variants of molybdenum carbide can be formed: α-Mo2C, η-MoC, or γ-MoC. The synthesized samples had a high specific surface area (7.1–203.0 m2/g) and meso- and microporosity. The samples also showed high catalytic activity during the dry reforming of methane. The proposed synthesis method is simple and variable and can be successfully used to obtain both Mo2C-based powder and supports catalysts.

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Gavrilova, Natalia, Maria Myachina, Victor Dyakonov, Victor Nazarov y Valery Skudin. "Synthesis of Microporous Mo2C-W2C Binary Carbides by Thermal Decomposition of Molybdenum-Tungsten Blues". Nanomaterials 10, n.º 12 (4 de diciembre de 2020): 2428. http://dx.doi.org/10.3390/nano10122428.

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Molybdenum and tungsten carbides are perspective catalytic systems. Their activity in many reactions is comparable to the activity of platinum group metals. The development of the synthesis method for of highly dispersed binary molybdenum and tungsten carbides is an important task. Dispersions of molybdenum-tungsten blue were used as a precursor for synthesis of binary molybdenum and tungsten carbides. The synthesis of carbides was carried out by thermal decomposition of molybdenum-tungsten blue xerogels in an inert atmosphere. The binary carbides were characterized by XRD, TGA, SEM and nitrogen adsorption. The influence of the molar ratio reducing agent/Me [R]/[ΣMe], molar ratio molybdenum/tungsten [Mo]/[W] on phase composition, and morphology and porous structure of binary carbides was investigated. Samples of binary molybdenum and tungsten carbides with a highly developed porous structure and a specific surface area were synthesized.

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Tišler, Zdeněk, Romana Velvarská, Lenka Skuhrovcová, Lenka Pelíšková y Uliana Akhmetzyanova. "Key Role of Precursor Nature in Phase Composition of Supported Molybdenum Carbides and Nitrides". Materials 12, n.º 3 (29 de enero de 2019): 415. http://dx.doi.org/10.3390/ma12030415.

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In this work, we studied the effect of molybdenum precursors and the synthesis conditions on the final phase composition of bulk and supported molybdenum carbides and nitrides. Ammonium heptamolybdate, its mixture with hexamethylenetetramine, and their complex were used as the precursors at different temperatures. It was investigated that the synthesis of the target molybdenum nitrides strongly depended on the structure of the precursor and temperature conditions, while the synthesis of carbide samples always led to the target phase composition. Unlike the carbide samples, where the α-Mo2C phase was predominant, the mixture of β-Mo2N, MoO2 with a small amount of metal molybdenum was generally formed during the nitridation. All supported samples showed a very good dispersion of the carbide or nitride phases.

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S. Maksymova, V. Voronov, P. Kovalchuk y A. Larionov. "Structure and Properties of Graphite-Molybdenum Brazed Joints". Metallurgical and Materials Engineering 29, n.º 1 (31 de marzo de 2023): 115–28. http://dx.doi.org/10.56801/mme989.

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The paper presents the results of X-ray microspectral studies of dissimilar brazed joints of molybdenum with graphite. It is shown that during active brazing of graphite with molybdenum, mutual diffusion processes occur, and the adhesion-active brazing filler metals penetrates into graphite, and interacts with it, which leads to the formation of carbide phases. When using the Ti-Cr-V and Cu-Ti-Ni systems brazing filler metals, titanium carbides are formed. The zirconium carbides are formed, when using the brazing filler metals based on the Zr-Pd(Mo) systems and the CxMey(Mo, Cr) carbides are formed using the brazing filler metals of the Pd-Ni-Cr-Ge system. The results of tests for three-point bending showed that the using of Pd-Ni-Cr-Ge brazing filler metals provides stable strength at the level of 34-37 MPa, destruction occurs along graphite.

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Thuvander, Mattias, Hans Magnusson y Ulrika Borggren. "Carbide Precipitation in a Low Alloyed Steel during Aging Studied by Atom Probe Tomography and Thermodynamic Modeling". Metals 11, n.º 12 (13 de diciembre de 2021): 2009. http://dx.doi.org/10.3390/met11122009.

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Carbide precipitation in martensitic low alloyed steels contributes to the mechanical properties through precipitation hardening. A high number density of carbides is desired to maximize the hardening effect, which is achieved through the precipitation of carbides on the dislocations in the martensitic structure. In this study, the nucleation, growth, and coarsening of vanadium and molybdenum carbides during aging at 600 °C for periods up to four weeks were investigated. The work covers characterization with atom probe tomography, which showed that the nucleation of V and Mo rich MC/M2C carbides takes place on dislocations. The growth of these carbides proceeds by the diffusion of elements to the dislocations, which has been modeled using Dictra software, confirming the rate of the reaction as well as the depletion of carbide formers in the matrix. For longer aging times, particle coarsening will decrease the number density of particles with a transition from dislocation-based carbides to separate rounded carbides.

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Papaefthymiou, Spyros, Marianthi Bouzouni y Roumen H. Petrov. "Study of Carbide Dissolution and Austenite Formation during Ultra–Fast Heating in Medium Carbon Chromium Molybdenum Steel". Metals 8, n.º 8 (16 de agosto de 2018): 646. http://dx.doi.org/10.3390/met8080646.

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In this study, UltraFast Heat Treatment (UFHT) was applied to a soft annealed medium carbon chromium molybdenum steel. The specimens were rapidly heated and subsequently quenched in a dilatometer. The resulting microstructure consists of chromium-enriched cementite and chromium carbides (in sizes between 5–500 nm) within fine (nano-sized) martensitic and bainitic laths. The dissolution of carbides in austenite (γ) during ferrite to austenite phase transformation in conditions of rapid heating were simulated with DICTRA. The results indicate that fine (5 nm) and coarse (200 nm) carbides dissolve only partially, even at peak (austenitization) temperature. Alloying elements, especially chromium (Cr), segregate at austenite/carbide interfaces, retarding the dissolution of carbides and subsequently austenite formation. The sluggish movement of the austenite /carbide interface towards austenite during carbide dissolution was attributed to the partitioning of Cr nearby the interface. Moreover, the undissolved carbides prevent austenite grain growth at peak temperature, resulting in a fine-grained microstructure. Finally, the simulation results suggest that ultrafast heating creates conditions that lead to chemical heterogeneity in austenite and may lead to an extremely refined microstructure consisting of martensite and bainite laths and partially dissolved carbides during quenching.

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Abdulazizov, Tilebaldy Adilovich, Abduraim Satyvaldievich Satyvaldiev y Kalyskan Imatali kyzy. "Oxidation of cubic complex carbides (Ti xVyMoz)C synthesis by electrospark dispersion method with atmospheric oxygen". E3S Web of Conferences 537 (2024): 05011. http://dx.doi.org/10.1051/e3sconf/202453705011.

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During the joint electrospark dispersion of titanium with VyMoz alloys in hexane, complex carbides (TixVyMoz)C with a cubic lattice are formed. Assuming that complex carbides (TixVyMoz)C as quasi-binary systems, where complex carbide (VyMoz)C with a cubic structure is dissolved in cubic titanium monocarbide, the composition of complex carbides (Ti0,75V0,05Mo0,20)C and (Ti0,65V0,31Mo0,04)C, formed by electrospark dispersion of Ti-V0,2Mo0,8 and Ti-V0,2Mo0,8 pairs. Using the method of differential thermal analysis, it was shown that the thermal stability against oxidation of complex carbides (TixVyMoz)C, synthesized by joint electrospark dispersion of titanium and the VyMoz alloy, depends on the ratio of metals. Thermal stability against oxidation increases with an increase in the content of titanium and molybdenum in the composition of complex carbides; their resistance to oxidation increases. It has been established that intensive oxidation of complex carbide (Ti0,75V0,05Mo0,20)C occurs at 595oC, and complex carbide (Ti0,65V0,31Mo0,04)C oxidizes at the maximum rate at 520oC.

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Chen, Meng, Yufei Ma, Yanqiang Zhou, Changqing Liu, Yanlin Qin, Yanxiong Fang, Guoqing Guan, Xiumin Li, Zhaoshun Zhang y Tiejun Wang. "Influence of Transition Metal on the Hydrogen Evolution Reaction over Nano-Molybdenum-Carbide Catalyst". Catalysts 8, n.º 7 (22 de julio de 2018): 294. http://dx.doi.org/10.3390/catal8070294.

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The highly efficient electrochemical hydrogen evolution reaction (HER) provides a promising way to solve energy and environment problems. In this work, various transition metals (Fe, Co, Ni, Cu, Ag, and Pt) were selected to support on molybdenum carbides by a simple organic-inorganic precursor carburization process. X-ray diffraction (XRD) analysis results indicated that the β-Mo2C phase was formed in all metal-doped samples. X-ray photoelectron spectroscopy analysis indicated that the binding energy of Mo2+ species (Mo2C) shifted to a lower value after metal was doped on the molybdenum carbide surface. Comparing with pure β-Mo2C, the electrocatalytic activity for HER was improved by transition metal doping on the surface. Remarkably, the catalytic activity improvement was more obvious when Pt was doped on molybdenum carbide (2% Pt-Mo2C). The 2% Pt-Mo2C required a η10 of 79 mV, and outperformed that of pure β-Mo2C (η10 = 410 mV) and other transition metal doped molybdenum carbides, with a small Tafel slope (55 mV/dec) and a low onset overpotential (32 mV) in 0.5 M H2SO4. Also, the 2% Pt-Mo2C catalyst demonstrated a high stability for the HER in 0.5 M H2SO4. This work highlights a feasible strategy to explore efficient electrocatalysts with low cost via engineering on the composition and nanostructure.

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Covington, Leroy, Kamalesh Munirathinam, Akand Islam y Kenneth Roberts. "Synthesis and characterization of nanostructured molybdenum & tungsten carbide materials, and study of diffusion model". Polish Journal of Chemical Technology 14, n.º 1 (1 de enero de 2012): 28–34. http://dx.doi.org/10.2478/v10026-012-0055-8.

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Synthesis and characterization of nanostructured molybdenum & tungsten carbide materials, and study of diffusion model Powders of two molybdenum carbides (Mo2C and MoC1-x) and tungsten carbide (WC) were prepared by means of temperature programmed reaction (TPR) method. Mo2C and MoC1-x were synthesized by reacting MoO3 with a preselected molar ratio of methane/hydrogen and carbon monoxide/hydrogen gas mixtures respectively. WC was prepared using tungsten oxide (WO3) and a methane/hydrogen gas mixture. These carbides were ultrasonically dispersed in de-ionized water. Samples were characterized using room temperature x-ray diffraction and scanning microscopy. A kinetic diffusion model is also studied to determine diffusivities in solids where the diffusing species desorbs or reacts at the external surfaces, and where the diffusivity does not vary appreciably with concentrations. The method involves measuring the flux of the diffusive species into the solid under the influence of a temperature program.

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Novák, Pavel, Kateřina Nová, Lucyna Jaworska y Andrei Shishkin. "Identification of Carbides in Tool Steel by Selective Etching". Defect and Diffusion Forum 395 (agosto de 2019): 55–63. http://dx.doi.org/10.4028/www.scientific.net/ddf.395.55.

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This paper describes simple metallographic technique for selective etching of individual types of carbides (MC, M2C and M6C and M7C3) in tool steel. Electrolytic etching in chromic acid was used in order to reveal the MC carbides. Chemical etching in permanganate solution revealed the M2C and M6C carbides, while the electrolytic etching in the latter solution enabled to observe M7C3, M2C and M6C carbides. These techniques were demonstrated on an experimental niobium-containing tool steel prepared by powder metallurgy. The results confirm that the MC carbides are highly thermally stable, while the M2C carbides decompose during austenitizing at the temperature of 1050 °C and higher. The M7C3 carbides dissolve in the austenite significantly. This exact and simple observation of the carbides behaviour enables to describe the role of particular carbides on heat treatment behaviour and also to save the carbide-forming elements, where the important ones (tungsten, vanadium) are listed as critical raw materials and the others (chromium and molybdenum) are also strategic.

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Teixeira da Silva, V. L. S., M. Schmal, V. Schwartz y S. T. Oyama. "Synthesis of a Mo/Nb mixed carbide". Journal of Materials Research 13, n.º 7 (julio de 1998): 1977–88. http://dx.doi.org/10.1557/jmr.1998.0278.

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Molybdenum and niobium carbides (β−Mo2C, NbC), as well as mixed carbides of molybdenum and niobium, were synthesized by the temperature-programmed carburization method (TPC) using a 20 vol% CH4/H2 gas mixture. The starting materials were MoO3, B-Nb2O5, and physical mixtures of B-Nb2O5/MoO3 with Nb/(Nb + Mo) atomic ratios varying from 0.2 to 0.8, respectively. Results from catalytic and temperatureprogrammed oxidation (TPO) measurements indicate that during the carburization of the Nb2O5/MoO3 physical mixture with Nby(Nb + Mo) = 0.8 there is, besides β−Mo2C and NbC formation, the appearance of a carbidic phase not detectable by x-ray diffraction (XRD). This phase appears to be highly active and selective for the dibenzothiophene hydrodesulfurization (HDS) reaction.

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Dongil, Ana Belén, Elodie Blanco, Juan José Villora-Picó, Antonio Sepúlveda-Escribano y Inmaculada Rodríguez-Ramos. "Effect of the Carbon Support and Conditions on the Carbothermal Synthesis of Cu-Molybdenum Carbide and Its Application on CO2 Hydrogenation to Methanol". Nanomaterials 12, n.º 7 (23 de marzo de 2022): 1048. http://dx.doi.org/10.3390/nano12071048.

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The synthesis of methanol by carbon dioxide hydrogenation has been studied using copper-molybdenum carbides supported on high surface area graphite, reduced graphene oxide and carbon nanotubes. The synthesis conditions and the effect of the support were studied. The catalysts were prepared in situ using H2 or He at 600 °C or 700 °C. Both molybdenum carbide and oxycarbide were obtained. A support with less reactive carbon resulted in lower proportion of carbide obtained. The best results were achieved over a 5 wt.% Cu and 10 wt.% Mo on high surface area graphite that reached 96.3% selectivity to methanol.

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Moser, Mathias, Sylvain Lorand, Florian Bussiere, Frédéric Demoisson, Hervé Couque y Frédéric Bernard. "Influence of Carbon Diffusion and the Presence of Oxygen on the Microstructure of Molybdenum Powders Densified by SPS". Metals 10, n.º 7 (14 de julio de 2020): 948. http://dx.doi.org/10.3390/met10070948.

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Due to molybdenum’s Body-Centered Cubic (BCC) crystalline structure, its ductile–brittle transition temperature is sensitive to shaping, purity and microstructure. Dense molybdenum parts are usually shaped by the powder metallurgy process. The aim of this work concerns the spark plasma sintering of high-purity powders prepared by inductively coupled plasma. The influence of carbon diffusion and its interaction with oxygen on the density (i.e., the densification stage) and on the microstructure (i.e., the grain growth stage) during spark plasma sintering was investigated. The formation of carbide is usually expected for a sintering temperature above 1500 °C leading to grain growth (e.g., more than 10 times larger than the initial powder grain size after sintering at 1900 °C for 10 min). The brittleness was also affected by the segregation of molybdenum carbides at the grain boundaries (i.e., intergranular brittle fracture). Consequently, to reduce the sintering temperature to below 1500 °C, mechanically activated powders were used. From these milled powders, a dense molybdenum disc (60 mm in diameter and 10 mm in thickness) sintered at 1450 °C under a pressure of 70 MPa for 30 min was obtained. It is composed of a fine microstructure without carbide and oxide, its ductility is close to 13% with a maximum resistance of 550 MPa.

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Chen, Tzung Ming, Yuan Ching Lin y Jiun Nan Chen. "Analysis of Wear Behaviour of Sintering Carbide against DLC Coated and Nitriding Steel". Advanced Materials Research 579 (octubre de 2012): 60–67. http://dx.doi.org/10.4028/www.scientific.net/amr.579.60.

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In this paper, tribological behaviours for sintering carbides and DLC/nitride film are discussed. During the wear test, two types of hardened steel are setting to sliding against eight series of carbide specimens in order to compare the wear mode and evaluate the wear performance of sintering carbides, which are made by different process parameters. The experiment result shows that a density ratio of sintering carbide between 86% and 99% does not have obviously different effect on wear resistance. Moreover, molybdenum binder with high diffusibility can improve the wear performance of tungsten carbide, but wear performance of titanium carbide is dependent on the amount of nickel/cobalt binder, separately. On the other hand, SAE52100 substrate absorbs the heat of friction and maintains the coated diamond-like carbon film in an excellent wear performance.

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Gnesin, B. A., M. I. Karpov, I. M. Aristova, I. B. Gnesin, D. V. Prokhorov, E. Yu Postnova, V. I. Vnukov, I. S. Zheltyakova y T. S. Stroganova. "Evolyutsiya defektov pri kholodnoy prokatke nizkolegirovannykh splavov molibdena". Микология и фитопатология, n.º 5 (15 de diciembre de 2023): 60–70. http://dx.doi.org/10.31857/s0869573323050075.

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The experimental work briefly describes the technology of multiple electron beam melting, which allows to obtain low-alloy molybdenum alloys with other carbide-forming elements and carbon. Two new alloys described in the work allow deformation by cold rolling up to a thickness of 0.17 mm. Based on the modified Golovin—Sims expression, it is shown that an alloy with dispersed carbides (size 30-200 nm) is strengthened during cold rolling much stronger than an alloy in which only large (≥1 microns) carbides are present. The evolution of continuity defects during cold rolling with an increase in the degree of deformation is traced.

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Tominaga, Hiroyuki, Yusuke Aoki y Masatoshi Nagai. "Hydrogenation of CO on molybdenum and cobalt molybdenum carbides". Applied Catalysis A: General 423-424 (mayo de 2012): 192–204. http://dx.doi.org/10.1016/j.apcata.2012.02.041.

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18

Zhang, Fu, Wenkai Zheng, Yanfu Lu, Lavish Pabbi, Kazunori Fujisawa, Ana Laura Elías, Anna R. Binion et al. "Superconductivity enhancement in phase-engineered molybdenum carbide/disulfide vertical heterostructures". Proceedings of the National Academy of Sciences 117, n.º 33 (29 de julio de 2020): 19685–93. http://dx.doi.org/10.1073/pnas.2003422117.

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Stacking layers of atomically thin transition-metal carbides and two-dimensional (2D) semiconducting transition-metal dichalcogenides, could lead to nontrivial superconductivity and other unprecedented phenomena yet to be studied. In this work, superconducting α-phase thin molybdenum carbide flakes were first synthesized, and a subsequent sulfurization treatment induced the formation of vertical heterolayer systems consisting of different phases of molybdenum carbide—ranging from α to γ′ and γ phases—in conjunction with molybdenum sulfide layers. These transition-metal carbide/disulfide heterostructures exhibited critical superconducting temperatures as high as 6 K, higher than that of the starting single-phased α-Mo2C (4 K). We analyzed possible interface configurations to explain the observed moiré patterns resulting from the vertical heterostacks. Our density-functional theory (DFT) calculations indicate that epitaxial strain and moiré patterns lead to a higher interfacial density of states, which favors superconductivity. Such engineered heterostructures might allow the coupling of superconductivity to the topologically nontrivial surface states featured by transition-metal carbide phases composing these heterostructures potentially leading to unconventional superconductivity. Moreover, we envisage that our approach could also be generalized to other metal carbide and nitride systems that could exhibit high-temperature superconductivity.

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Czaplicka, Natalia, Andrzej Rogala y Izabela Wysocka. "Metal (Mo, W, Ti) Carbide Catalysts: Synthesis and Application as Alternative Catalysts for Dry Reforming of Hydrocarbons—A Review". International Journal of Molecular Sciences 22, n.º 22 (15 de noviembre de 2021): 12337. http://dx.doi.org/10.3390/ijms222212337.

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Dry reforming of hydrocarbons (DRH) is a pro-environmental method for syngas production. It owes its pro-environmental character to the use of carbon dioxide, which is one of the main greenhouse gases. Currently used nickel catalysts on oxide supports suffer from rapid deactivation due to sintering of active metal particles or the deposition of carbon deposits blocking the flow of gases through the reaction tube. In this view, new alternative catalysts are highly sought after. Transition metal carbides (TMCs) can potentially replace traditional nickel catalysts due to their stability and activity in DR processes. The catalytic activity of carbides results from the synthesis-dependent structural properties of carbides. In this respect, this review presents the most important methods of titanium, molybdenum, and tungsten carbide synthesis and the influence of their properties on activity in catalyzing the reaction of methane with carbon dioxide.

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Jandová, Dagmar, Pavel Šuchmann y Jana Nižňanská. "Microstructure of Tool Steel X37CrMoV5 after Cryogenic Treatment and its Effect on Wear Resistance". Key Engineering Materials 647 (mayo de 2015): 23–37. http://dx.doi.org/10.4028/www.scientific.net/kem.647.23.

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A deep cryogenic heat treatment (DCT) was applied to X37CrMoV5 steel, which included soaking at -160°C for 12 and 30 hours followed by tempering at 180°C. Microstructures were compared with those after conventional heat treatment (HT). Microstructures with conspicuous dendritic segregation were observed in all specimens. After HT coarser and finer tempered martensite occurred in depleted and enriched areas of carbon and alloying elements respectively. Coarse molybdenum and vanadium carbides, fine secondary Fe2MoC carbides and retained austenite were identified after HT. Deep freezing resulted in microstructure refinement, transformation of retained austenite into twinned martensite, spinodal decomposition of martensite plates and precipitation of semicoherent h-carbide. The mechanism of h-carbide precipitation was discussed. Wear rate was measured using pin-on-disc test. The best results were obtained after DCT with cryosoaking for 12 hours.

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Alshibane, I., S. Laassiri, J. L. Rico y J. S. J. Hargreaves. "Methane Cracking over Cobalt Molybdenum Carbides". Catalysis Letters 148, n.º 6 (21 de abril de 2018): 1643–50. http://dx.doi.org/10.1007/s10562-018-2378-4.

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22

Chrysanthou, A. y P. Grieveson. "The observation of metastable molybdenum carbides". Journal of Materials Science Letters 10, n.º 3 (febrero de 1991): 145–46. http://dx.doi.org/10.1007/bf02352830.

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23

Glotka, O. "Prediction carbides composition in nickel-based superalloys directional crystallization". Innovative Materials and Technologies in Metallurgy and Mechanical Engineering, n.º 2 (18 de marzo de 2021): 13–21. http://dx.doi.org/10.15588/1607-6885-2020-2-2.

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Objective. To study the specifics of the distribution of alloying elements in the carbides of the multicomponent system Ni-5Cr-9Co-6Al-1Ti-11.7W-1.1Mo-1.6Nb-0.15C by directional crystallization, using the calculated method of CALPHAD prediction. Research methods. To find regularities and calculate the distribution of alloying elements in the alloy, the latest CALPHAD method was chosen, and modeling of thermodynamic processes of phase crystallization was performed. The obtained results. The results of thermodynamic calculations of the chemical composition of carbides are given in the form of mathematical dependences. The equation of the influence of alloying elements on the dissolution (release) temperature of carbides is obtained. It is shown that the obtained dependences are closely correlated with the thermodynamic processes occurring in the system. Scientific novelty. It is shown that with increasing total concentration of carbide-forming elements, the chemical composition of carbides becomes more complicated. The titanium content of more than 2% leads to an increase in the temperature of the carbide liquidus, and at 4.5 % topologically densely packed phases is formed. When the concentration of molybdenum in the alloy is more than 4%, the probability of precipitating topologically close-packed phases in the structure increases markedly, which negatively affects the mechanical properties and heat resistance. Practical value. Based on an integrated approach for multicomponent heat-resistant nickel-based alloys, new regression models were obtained that allow adequately predict the chemical composition of carbides by the chemical composition of the alloy, which allowed to solve the problem of calculated prediction of carbide composition by chemical composition of the alloy.

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Henderer, W. E. "Relationship Between Alloy Composition and Tool-Life of High-Speed Steel Twist Drills". Journal of Engineering Materials and Technology 114, n.º 4 (1 de octubre de 1992): 459–64. http://dx.doi.org/10.1115/1.2904199.

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Tool-life tests are reported which show the relationship between the alloy composition of high-speed steel twist drills and performance. Tool-life is shown to depend primarily on the composition of the matrix consisting of tempered martensite and precipitated secondary carbides. The longest tool-life was obtained from alloys with high vanadium content and low tungsten or molybdenum content. This observation is consistent with the dispersion characteristics of vanadium carbide which precipitate during tempering.

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Myachina, Maria, Natalia Gavrilova, Ksenia Poluboyarinova y Victor Nazarov. "Molybdenum–Tungsten Blue Nanoparticles as a Precursor for Ultrafine Binary Carbides". Nanomaterials 11, n.º 3 (17 de marzo de 2021): 761. http://dx.doi.org/10.3390/nano11030761.

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Herein, we demonstrate a promising method for the synthesis of ultrafine carbide particles using dispersions of molybdenum–tungsten nanoparticles. Dispersions of molybdenum–tungsten blue nanoparticles with different initial molar ratios of molybdenum/tungsten were synthesized through the reduction of molybdate and tungstate ions by ascorbic acid in an acidic medium (pH = 1.0–2.5). Molybdenum–tungsten blue nanoparticles were characterized by ultraviolet–visual (UV–VIS), infrared (FTIR), and X-ray photoelectron (XPS) spectroscopies; transmission electronic microscopy (TEM); and dynamic light scattering (DLS). We demonstrated that molybdenum–tungsten blue nanoparticles belong to toroidal polyoxometalate clusters (λmax = 680–750 nm) with a predominant particle size of 4.0 nm. Molybdenum–tungsten blue dispersions were shown to be monodispersed systems with a small particle size and long-term stability (>30 days) and are suitable for further catalytic applications.

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Nykiel, Tadeusz y Tadeusz Hryniewicz. "Effect of High-Temperature Heating on Chemical Changes in M₇C₃ Carbides of AISI D2 Tool Steel". International Letters of Chemistry, Physics and Astronomy 36 (julio de 2014): 258–71. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.36.258.

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The paper presents the study results obtained on 16H12MF/NC11LV/D2 tool steel. The main purpose of the study was to establish the chemical composition of the coarse primary M7C3 carbides occurring in that steel after a standard soft annealing. The effect of high-temperature annealing in the air atmosphere was investigated. The study was limited to the decarburized layer, on the distance of about 0.4 mm from the surface, of hardened steel after annealing and austenitizing at 1150 °C in the air atmosphere for the periods of 30 and 90 minutes. It was found that the coarse primary M7C3 carbides of the annealed D2 tool steel differ significantly as to the contents of Cr, Mo, and V, and in the most degree to the contents of chromium and molybdenum. The average concentration of chromium rises successively with the growth of austenitizing time. On the other hand, the concentrations of molybdenum and vanadium are lower after 30 minutes of austenitizing than their concentrations in the similar carbides of the annealed steel. Prolongation of the austenitizing time up to 90 minutes results in the increase of molybdenum and vanadium contents in the coarse carbides. It was found that austenitizing of AISI D2 tool steel at the temperature of 1150 °C in the air atmosphere leads to precipitation of the second phase, brighter in the BSE_Z pictures, in relation to the matrix of carbides, with the amount and magnitude being higher with the annealing time.

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Nykiel, Tadeusz y Tadeusz Hryniewicz. "Effect of High-Temperature Heating on Chemical Changes in M7C3 Carbides of AISI D2 Tool Steel". International Letters of Chemistry, Physics and Astronomy 36 (15 de julio de 2014): 258–71. http://dx.doi.org/10.56431/p-6203wy.

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The paper presents the study results obtained on 16H12MF/NC11LV/D2 tool steel. The main purpose of the study was to establish the chemical composition of the coarse primary M7C3 carbides occurring in that steel after a standard soft annealing. The effect of high-temperature annealing in the air atmosphere was investigated. The study was limited to the decarburized layer, on the distance of about 0.4 mm from the surface, of hardened steel after annealing and austenitizing at 1150 °C in the air atmosphere for the periods of 30 and 90 minutes. It was found that the coarse primary M7C3 carbides of the annealed D2 tool steel differ significantly as to the contents of Cr, Mo, and V, and in the most degree to the contents of chromium and molybdenum. The average concentration of chromium rises successively with the growth of austenitizing time. On the other hand, the concentrations of molybdenum and vanadium are lower after 30 minutes of austenitizing than their concentrations in the similar carbides of the annealed steel. Prolongation of the austenitizing time up to 90 minutes results in the increase of molybdenum and vanadium contents in the coarse carbides. It was found that austenitizing of AISI D2 tool steel at the temperature of 1150 °C in the air atmosphere leads to precipitation of the second phase, brighter in the BSE_Z pictures, in relation to the matrix of carbides, with the amount and magnitude being higher with the annealing time.

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Jothi, Palani R., Yuemei Zhang, Jan P. Scheifers, Hyounmyung Park y Boniface P. T. Fokwa. "Molybdenum diboride nanoparticles as a highly efficient electrocatalyst for the hydrogen evolution reaction". Sustainable Energy & Fuels 1, n.º 9 (2017): 1928–34. http://dx.doi.org/10.1039/c7se00397h.

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Non-noble metal nanomaterials (molybdenum sulfides, phosphides, carbides, and nitrides) have recently emerged as highly active electrocatalysts for the hydrogen evolution reaction (HER). Here we present experimental and theoretical studies of the first highly active molybdenum boride nanomaterial for the HER.

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Waki, T., S. Terazawa, Y. Umemoto, Y. Tabata, Y. Murase, M. Kato, K. Hirota y H. Nakamura. "Magnetic susceptibility ofη-carbide-type molybdenum and tungsten carbides and nitrides". Journal of Physics: Conference Series 344 (14 de marzo de 2012): 012017. http://dx.doi.org/10.1088/1742-6596/344/1/012017.

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30

Mladenović, Dušan, Milica Vujković, Slavko Mentus, Diogo M. F. Santos, Raquel P. Rocha, Cesar A. C. Sequeira, Jose Luis Figueiredo y Biljana Šljukić. "Carbon-Supported Mo2C for Oxygen Reduction Reaction Electrocatalysis". Nanomaterials 10, n.º 9 (10 de septiembre de 2020): 1805. http://dx.doi.org/10.3390/nano10091805.

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Molybdenum carbide (Mo2C)-based electrocatalysts were prepared using two different carbon supports, commercial carbon nanotubes (CNTs) and synthesised carbon xerogel (CXG), to be studied from the point of view of both capacitive and electrocatalytic properties. Cation type (K+ or Na+) in the alkaline electrolyte solution did not affect the rate of formation of the electrical double layer at a low scan rate of 10 mV s−1. Conversely, the different mobility of these cations through the electrolyte was found to be crucial for the rate of double-layer formation at higher scan rates. Molybdenum carbide supported on carbon xerogel (Mo2C/CXG) showed ca. 3 times higher double-layer capacity amounting to 75 mF cm−2 compared to molybdenum carbide supported on carbon nanotubes (Mo2C/CNT) with a value of 23 mF cm−2 due to having more than double the surface area size. The electrocatalytic properties of carbon-supported molybdenum carbides for the oxygen reduction reaction in alkaline media were evaluated using linear scan voltammetry with a rotating disk electrode. The studied materials demonstrated good electrocatalytic performance with Mo2C/CXG delivering higher current densities at more positive onset and half-wave potential. The number of electrons exchanged during oxygen reduction reaction (ORR) was calculated to be 3, suggesting a combination of four- and two-electron mechanism.

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Puello-Polo, Esneyder, Mónica V. Ayala y Joaquín L. Brito. "Activated carbon supported cobalt-molybdenum carbides: effect of the synthesis method, heating rate, type of cobalt precursor and presulfiding agent on thiophene hydrodesulfurization". Revista Facultad de Ingeniería Universidad de Antioquia, n.º 70 (12 de febrero de 2014): 75–85. http://dx.doi.org/10.17533/udea.redin.14249.

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This work studied the Effect of the presulfiding agent, type of precursor (sulfate vs. nitrate of promotor), synthesis method (conventional vs. carbothermal carbiding) and heating rate in the hydrodesulfurization of thiophene over activated carbon supported cobalt-molybdenum carbides. The synthesis was carried out using the methods conventional (CH4/H2 (1:4)) and carbothermal with H2 at 973 K and 1 or 5 K/min. The carbided phases were characterized by surface area (B.E.T), X-ray Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The surface areas were within a rank of 266 and 493m2/g, whereas the XRD analysis verified the presence of Co6Mo6C2 for carbides obtained by carbothermal method independently of these variables. The XPS showed the presence on the surface of: Moδ+, Mo4+and Mo6+, and Co2+ whose abundance was influenced by the synthesis method and type of precursor. On the order hand, XPS revealed that the carbides obtained by sulfate precursor retained sulfur on the surface as S2- and SO42-. Tests of thiophene HDS showed that carbides obtained by the carbothermal method had higher activity than those obtained by the conventional method when it was activated with CS2/H2 and inversely when used H2S/H2.

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Caroff, Théo, Pitalinani Badaki, Nathalie Herbert, Franck Tessier, David Berthebaud, Naoki Ohashi, Tetsuo Uchikoshi, Pierre Lonchambon, Nathalie Herlin-Boime y Fabien Grasset. "Facile Synthesis and Characterization of Molybdenum Carbides/Carbon Nanocomposites by Laser Pyrolysis". Nanomanufacturing 2, n.º 3 (8 de agosto de 2022): 112–23. http://dx.doi.org/10.3390/nanomanufacturing2030009.

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This short communication reports on the facile and scalable synthesis and characterization of molybdenum carbides/carbon nanocomposites prepared by laser pyrolysis in a one-step process. Water and commercial molybdenum oxide were used as low-cost environmentally friendly precursors. The nanocomposites are mainly composed of two types of carbides with different apparent crystallite sizes, 21 ± 1 nm and 9 ± 1 nm for Mo2C and MoC1−x, respectively. Thanks to a simple annealing at 500 °C under argon, it was possible to increase the specific surface area around 50 m2/g without changing the morphology of the nanocomposite.

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Bober, Mariusz, Jacek Senkara y Bogdan Wendler. "Persistence of the thin layers of transition metal carbides in contact with liquid NiBSi alloy". Welding Technology Review 93, n.º 1 (27 de febrero de 2021): 5–12. http://dx.doi.org/10.26628/wtr.v93i1.1128.

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The article presents the results of study on interaction between the liquid NiBSi alloy and solid, thin, micrometer-range layers of transition metal carbides of IVB - VIB groups of the periodic table. The reactive magnetron sputtering method was adopted to deposit of these layers on molybdenum substrates. Carbide layers are destroyed in contact with liquid alloy by dissolving, intensified by the penetration of the liquid along the coating - substrate interface. The strong interaction between liquid NiBSi and both the carbide ceramics and the refractory metal substrate was revealed. The effect intensity differs somewhat for both tested carbide groups: IVB (relatively fast) and VIB (less intense).

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Nazari, Ali y Shadi Riahi. "Failure analysis of heat treated HSLA wheel bolt steels". Multidiscipline Modeling in Materials and Structures 6, n.º 3 (24 de septiembre de 2010): 373–82. http://dx.doi.org/10.1108/15736101011080114.

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PurposeThe aims of this study is to analyze failure of two types of high‐strength low‐alloy (HSLA) steels which are used in wheel bolts 10.9 grade, boron steel and chromium‐molybdenum steel, before and after heat treatment.Design/methodology/approachThe optimum heat treatment to obtain the best tensile behavior was determined and Charpy impact and Rockwell hardness tests were performed on the two steel types before and after the optimum heat treating.FindingsFractographic studies show a ductile fracture for heat‐treated boron steel while indicate a semi‐brittle fracture for heat‐treated chromium‐molybdenum steel. Formation of a small boron carbide amount during heat treating of boron steel results in increment the bolt's tensile strength while the ductility did not changed significantly. In the other hand, formation of chromium and molybdenum carbides during heat treating of chromium‐molybdenum steel increased the bolt's tensile strength with a considerable reduction in the final ductility.Originality/valueThis paper evaluates failure analysis of HSLA wheel bolt steels and compares their microstructure before and after the loading regime.

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Führer, M., T. van Haasterecht y J. H. Bitter. "Molybdenum and tungsten carbides can shine too". Catalysis Science & Technology 10, n.º 18 (2020): 6089–97. http://dx.doi.org/10.1039/d0cy01420f.

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In this perspective, we argue that transition metal carbides such as molybdenum and tungsten hold great potential for the catalytic conversions of future feedstocks due to their ability to remain active in the presence of impurities in the feedstock.

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Karuppasamy, K., A. Nichelson, Dhanasekaran Vikraman, Jun-Hyeok Choi, Sajjad Hussain, C. Ambika, Ranjith Bose, Akram Alfantazi y Hyun-Seok Kim. "Recent Advancements in Two-Dimensional Layered Molybdenum and Tungsten Carbide-Based Materials for Efficient Hydrogen Evolution Reactions". Nanomaterials 12, n.º 21 (3 de noviembre de 2022): 3884. http://dx.doi.org/10.3390/nano12213884.

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Green and renewable energy is the key to overcoming energy-related challenges such as fossil-fuel depletion and the worsening of environmental habituation. Among the different clean energy sources, hydrogen is considered the most impactful energy carrier and is touted as an alternate fuel for clean energy needs. Even though noble metal catalysts such as Pt, Pd, and Au exhibit excellent hydrogen evolution reaction (HER) activity in acid media, their earth abundance and capital costs are highly debatable. Hence, developing cost-effective, earth-abundant, and conductive electrocatalysts is crucial. In particular, various two-dimensional (2D) transition metal carbides and their compounds are gradually emerging as potential alternatives to noble metal-based catalysts. Owing to their improved hydrophilicity, good conductivity, and large surface areas, these 2D materials show superior stability and excellent catalytic performances during the HER process. This review article is a compilation of the different synthetic protocols, their impact, effects of doping on molybdenum and tungsten carbides and their derivatives, and their application in the HER process. The paper is more focused on the detailed strategies for improving the HER activity, highlights the limits of molybdenum and tungsten carbide-based electrocatalysts in electro-catalytic process, and elaborates on the future advancements expected in this field.

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Li, Yusheng, Mian Wang, Yupeng Wang, Xing Wei, Wenli Ren, Xulong Ren y Zhibo Li. "Effect of alloy composition on the 45 steel microstructure and properties of scanning electron beam surface alloying". Journal of Physics: Conference Series 2691, n.º 1 (1 de enero de 2024): 012070. http://dx.doi.org/10.1088/1742-6596/2691/1/012070.

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Abstract In order to improve the surface properties of 45 steel, the effects of different scanning electron beam treatments on the surface properties of 45 steel were studied. The research results indicate that after scanning electron beam surface alloying (SEBSA) treatment, in addition to forming needle like martensite, carbides (tungsten carbide and molybdenum carbide) also exist in the alloying zone of the strengthening layer, moreover, the grains become finer. After scanning electron beam alloying treatment, the surface hardness reached 1250HV, which is 5-6 times the substrate. Compared with the wear loss of the matrix, the wear resistance of the sample after SEBSA treatment increased by nearly six times.

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Vasilevich, A. V., O. N. Baklanova y A. V. Lavrenov. "Molybdenum Carbides: Synthesis and Application in Catalysis". Solid Fuel Chemistry 54, n.º 6 (noviembre de 2020): 354–61. http://dx.doi.org/10.3103/s0361521920060130.

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39

Wang, Zhen H., Da Li, Dianyu Geng, Song Ma, Wei Liu y Z. D. Zhang. "Magnetic and electronic transport properties of nanocomposites of superconducting Mo carbides’ nanoparticles embedded in a ferromagnetic carbon matrix". Journal of Materials Research 24, n.º 7 (julio de 2009): 2229–34. http://dx.doi.org/10.1557/jmr.2009.0295.

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The electronic transport and magnetic properties of nanocomposites, in which nanoparticles of superconducting (SC) molybdenum carbides are embedded in a ferromagnetic (FM) carbon matrix to form a three-dimensional SC-FM network, are studied. The high-resolution transmission electron microscope observation shows that the carbon in the nanocomposites is in both ordered and disordered forms. The magnetic properties of the nanocomposites are ruled by the ferromagnetic carbon matrix. The temperature dependence of electrical resistivity of the nanocomposites is dominated by the carbon matrix, showing the semi-conductivity. The special I-V curves near the zero voltage bias of the nanocomposites are observed at low temperatures, due to the influence of contact barriers between molybdenum carbides and the carbon matrix.

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Biedunkiewicz, A., P. Figiel, M. Krawczyk y U. Gabriel-Polrolniczak. "Simultaneous synthesis of molybdenum carbides and titanium carbides by sol–gel method". Journal of Thermal Analysis and Calorimetry 113, n.º 1 (30 de abril de 2013): 253–58. http://dx.doi.org/10.1007/s10973-013-3176-2.

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41

Shilov, Ivan, Andrey Smirnov, Olga Bulavchenko y Vadim Yakovlev. "Effect of Ni–Mo Carbide Catalyst Formation on Furfural Hydrogenation". Catalysts 8, n.º 11 (19 de noviembre de 2018): 560. http://dx.doi.org/10.3390/catal8110560.

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High-loading Ni–Mo carbide catalysts were prepared by the modified gel-combustion method under various thermal treatment conditions. All samples were studied by X-ray diffraction (XRD) analysis, which showed that the catalysts could contain cubic and hexagonal molybdenum carbides, nickel, nickel oxide and Ni–Mo solid solutions, depending on the thermal treatment conditions. Study of catalyst activity and selectivity in the hydrogenation of furfural was carried out in a batch reactor at 150 °C and hydrogen pressure 6.0 MPa. Analysis of the reaction products showed that the highest yields of 2-methylfuran (2-MF) and furfuryl alcohol (FA) were achieved using catalysts synthesized by calcination of the nickel-molybdenum-carbon precursor at 400 °С with the following reduction in a stream of hydrogen at 600 °C. The best results for production of FA with a yield of 80 mol % and 2-MF with a yield of 29 mol % were observed using Ni6MoC–SiO2 (400/600) and Ni1MoC–SiO2 (400/600) catalysts, respectively. It has been shown that the addition of nickel to the carbide molybdenum catalyst significantly increases the activity of the catalytic systems. In addition, nickel also contributes to the formation of products formed by hydrogenation of the aromatic ring tetrahydrofurfuryl alcohol (THFA) and 2-methyltetrahydrofuran (2-MTHF).

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Balbino, Nádia Alves Nery, Edmilson Otoni Corrêa, Danilo Roque Huanca, Flávio Amaury de Freitas Matos y Livio de Carvalho Valeriano. "Comparative Study of Corrosion Behaviors of WC-NiMo and WC-Co Cemented Carbides". Materials 16, n.º 12 (20 de junio de 2023): 4480. http://dx.doi.org/10.3390/ma16124480.

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In this paper, the influence of a nickel binder metal and molybdenum carbide as an additional alloying element on the microstructure and corrosion behavior of WC-based cemented carbides, processed by conventional powder metallurgy, was studied, and a comparison with conventional cemented carbide (WC-Co) was carried out. The sintered alloys were characterized, before and after corrosive tests, by analyses using optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The corrosion resistance of the cemented carbides was investigated by open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy in a 3.5 wt.% NaCl solution. The WC-NiMo cemented carbides showed microstructures similar to those of WC-Co; however, pores and binder islands were observed in the microstructures. The corrosion tests showed promising results, the WC-NiMo cemented carbide showed superior corrosion resistance and higher passivation capacity than the WC-Co cemented carbide. The WC-NiMo alloy showed a higher EOC ≈−0.18 V vs. Ag|AgCl|KCl3mol/L than the WC-Co (EOC≈−0.45 V vs. Ag|AgCl|KCl3mol/L). The potentiodynamic polarization curves showed lower current density values throughout the potential range for the WC-NiMo alloy, and it was observed that Ecorr was less negative (≈−0.416 V vs. Ag|AgCl|KCl3mol/L) than for WC-Co (≈−0.543 V vs. V vs. Ag|AgCl|KCl3mol/L). The EIS analysis confirmed low rate corrosion of WC-NiMo associated with the formation of a passive thin layer. This alloy showed a higher Rct (1970.70 Ω).

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Yang, Yuanyuan, Ruguang Wang, Liujing Yang, Yan Jiao y Tao Ling. "Two dimensional electrocatalyst engineering via heteroatom doping for electrocatalytic nitrogen reduction". Chemical Communications 56, n.º 91 (2020): 14154–62. http://dx.doi.org/10.1039/d0cc05635a.

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44

He, Chunyong y Juzhou Tao. "Exploration of the electrochemical mechanism of ultrasmall multiple phases molybdenum carbides nanocrystals for hydrogen evolution reaction". RSC Advances 6, n.º 11 (2016): 9240–46. http://dx.doi.org/10.1039/c5ra25367e.

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Ultrasmall multiple phases molybdenum carbides nanocrystals (down to 2.5 nm) on graphene support were synthesized by a simplein situmethod. These hybrids show extraordinary high HER activity in acid media.

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Cho, Soo-Yeon, Ju Ye Kim, Ohmin Kwon, Jihan Kim y Hee-Tae Jung. "Molybdenum carbide chemical sensors with ultrahigh signal-to-noise ratios and ambient stability". Journal of Materials Chemistry A 6, n.º 46 (2018): 23408–16. http://dx.doi.org/10.1039/c8ta07168c.

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46

He, Chunyong y Juzhou Tao. "Synthesis of nanostructured clean surface molybdenum carbides on graphene sheets as efficient and stable hydrogen evolution reaction catalysts". Chemical Communications 51, n.º 39 (2015): 8323–25. http://dx.doi.org/10.1039/c5cc01240f.

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47

Zhang, Chen, Siduo Wu, Shaochuan Luo, Yong Wang, Jingjing Li y Yan Leng. "Vanadium-doped molybdenum carbides as a promising catalyst for C–N/C–C coupling reactions". New Journal of Chemistry 44, n.º 23 (2020): 9736–42. http://dx.doi.org/10.1039/d0nj01593h.

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Vanadium-doped molybdenum carbides encapsulated in nitrogen-doped carbon exhibit significantly enhanced catalytic efficiency for both the oxidative C–N coupling of amines and C–C bond couplings of alcohols and ketones.

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Youssef, Mervat, Adel Nofal y Abdelhamid Hussein. "Influence of Cooling Rate on Nature and Morphology of Intercellular Precipitates in Si-Mo Ductile Irons". Materials Science Forum 925 (junio de 2018): 231–38. http://dx.doi.org/10.4028/www.scientific.net/msf.925.231.

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This work is designed to better understand the influence of cooling rate on the nature and morphology of intercellular precipitates in Silicon-Molybdenum ferritic ductile iron (SiMo). Plates of 3, 6, 9 mm thickness were cast in greensand and investment casting molds to give a wide spectrum of cooling rates. It was found that at higher cooling rates, the intercellular regions have a lamellar structure typical of pearlite. With decreasing cooling rates, the precipitate contains complex (Fe-Mo-Si) carbides of fine spheroidal or rod-like structure surrounding the eutectic carbides.Intensive Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS) and Optical Microscopy (OM) investigations showed that the eutectic carbides are mainly (Fe, Mo, Si) C containing up to 48% Mo, whereas the fine precipitates contain lower Mo-contents. Both carbide types did not show to have a strict stoichometric composition. The solidification and solid-state transformation path was determined using both phase diagram calculated from Thermo-Calc software as well as Differential Scanning Calorimetry (DSC).

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Li, Xiao, Xiao-Li Hu, Xin-Long Wang, Qing Qing Pan, Lei Liu y Zhong-Min Su. "A substrate-free Mo2C-based electrocatalyst by facile glucose-blowing for efficient hydrogen production". New Journal of Chemistry 43, n.º 48 (2019): 18970–74. http://dx.doi.org/10.1039/c9nj04598h.

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A catalyst Gb-Mo2C@PC, in which molybdenum carbides nanoparticles embedded into the 3D self-supported porous graphene shells, was reported. Gb-Mo2C@PC exhibits good HER performance in basic and acid electrolyte.

50

Huang, Qing, Xiaokun Li, Suxiang Feng, Wenfeng Zhuge, Fengping Liu, Jinyun Peng y Shancai Mo. "An electrochemical sensor based on the composite of molybdenum carbides and a multiwalled carbon nanotube modified electrode for the ultrasensitive detection of rifampicin". Analytical Methods 10, n.º 29 (2018): 3594–601. http://dx.doi.org/10.1039/c8ay00852c.

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The composite of molybdenum carbides and multiwalled carbon nanotube (MWCNTs–Mo₂C) modified glassy carbon electrode (GCE) was developed to prepare an electrochemical sensor for the ultrasensitive detection of rifampicin.

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