scholarly journals Synthesis of Metastable Ternary Pd-W and Pd-Mo Transition Metal Carbide Nanomaterials

Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6650
Author(s):  
James M. Thode ◽  
Daniel P. Harris ◽  
Cheng Wan ◽  
Brian M. Leonard
Keyword(s):  
Transition Metal ◽  
Hexagonal Phase ◽  
Transition Metal Carbide ◽  
Methanol Oxidation Reaction ◽  
Metal Carbides ◽  
New Materials ◽  
Ternary Carbide ◽  
Powder Samples ◽  
Co Precipitation ◽  
Synthetic Approaches

Research and catalytic testing of platinum group transition metal carbides have been extremely limited due to a lack of reliable, simple synthetic approaches. Powder samples have been reported to phase separately above 1%, and only thin-film samples have been reported to have appreciable amounts of precious metal doping. Herein, we demonstrated, through the simple co-precipitation of Pd and W or Mo precursors and their subsequent annealing, the possibility to readily form ternary carbide powders. During the investigation of the Pd-W ternary system, we discovered a new hexagonal phase, (PdW)2C, which represents the first non-cubic Pd ternary carbide. Additionally, the solubility of Pd in the Pd-W-C and Pd-Mo-C systems was increased to 24 and 32%, respectively. As a potential application, these new materials show an enhanced activity for the methanol oxidation reaction (MOR) compared to industrial Pd/C.

scholarly journals Tuning transition metal carbide activity by surface metal alloying: a case study on CO2capture and activation

2018 ◽  
Vol 20 (34) ◽  
pp. 22179-22186 ◽  
Author(s):  
Martí López ◽  
Luke Broderick ◽  
John J. Carey ◽  
Francesc Viñes ◽  
Michael Nolan ◽  
...  
Keyword(s):  
Transition Metal ◽  
Density Functional ◽  
State Of The Art ◽  
Transition Metal Carbide ◽  
Metal Carbide ◽  
Metal Carbides ◽  
Early Transition Metal ◽  
Transition Metal Carbides ◽  
Surface Metal

The CO2capture and activation on early transition metal carbides can be fine-tuned by surface doping of similar metals as evidenced by state-of-the-art density functional simulations of the adsorption and desorption rates on suited models.

Electric and Magnetic Properties of Transition-Metal Carbide Sc3TC4 (T=Co, Ru, Os)

2016 ◽  
Vol 257 ◽  
pp. 34-37
Author(s):  
Takuto Kazama ◽  
Minoru Maeda ◽  
Kouichi Takase ◽  
Yoshiki Takano ◽  
Tadataka Watanabe
Keyword(s):  
Phase Transition ◽  
Magnetic Properties ◽  
Phase Transitions ◽  
Transition Metal ◽  
Density Wave ◽  
Transition Metal Carbide ◽  
Superconducting Transition ◽  
Metal Carbides ◽  
Low Dimensional ◽  
Successive Phase

We investigate electric and magnetic properties of quasi-one-dimensional transition-metal carbides Sc3TC4 (T = Co, Ru, and Os), and their mixed crystals Sc3(Co1-xRux)C4 and Sc3(Ru1-xOsx)C4. Sc3CoC4 exhibits successive phase transitions of charge-density-wave transition at TCDW ~ 140 K, Peierls-like structural transition at Ts ~ 70 K, and superconducting transition at Tc ~ 5 K. Sc3RuC4 and Sc3OsC4 exhibit a phase transition at T* ~ 220 K and 250 K, respectively, which should occur in the low-dimensional electronic structure. For Sc3CoC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Co1-xRux)C4 that the phase transitions at TCDW, Ts, and Tc exhibit different robustness against Ru doping. For Sc3RuC4 and Sc3OsC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Ru1-xOsx)C4 that an identical kind of phase transition occurs at T*. Additionally, the present study reveals that the phase transition at T* in Sc3RuC4 and Sc3OsC4 is inherently different from the phase transitions at TCDW, Ts, and Tc in Sc3CoC4.

scholarly journals An Overview of Recent Advances in the Synthesis and Applications of the Transition Metal Carbide Nanomaterials

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 776
Author(s):  
Saba Ahmad ◽  
Iffat Ashraf ◽  
Muhammad Adil Mansoor ◽  
Syed Rizwan ◽  
Mudassir Iqbal
Keyword(s):  
Transition Metal ◽  
Good Stability ◽  
Transition Metal Carbide ◽  
Synthesis Methods ◽  
Metal Carbides ◽  
Modern Approach ◽  
Nano Powder ◽  
Two Factors ◽  
Recent Developments ◽  
Respective Field

Good stability and reproducibility are important factors in determining the place of any material in their respective field and these two factors also enable them to use in various applications. At present, transition metal carbides (TMCs) have high demand either in the two-dimensional (2D) form (MXene) or as nanocomposites, nanoparticles, carbide films, carbide nano-powder, and carbide nanofibers. They have shown good stability at high temperatures in different environments and also have the ability to show adequate reproducibility. Metal carbides have shown a broad spectrum of properties enabling them to engage the modern approach of multifacet material. Several ways have been routed to synthesize metal carbides in their various forms but few of those gain more attention due to their easy approach and better properties. TMCs find applications in various fields, such as catalysts, absorbents, bio-sensors, pesticides, electrogenerated chemiluminescence (ECL), anti-pollution and anti-bacterial agents, and in tumor detection. This article highlights some recent developments in the synthesis methods and applications of TMCs in various fields.

scholarly journals Phase controlled synthesis of transition metal carbide nanocrystals by ultrafast flash Joule heating

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Bing Deng ◽  
Zhe Wang ◽  
Weiyin Chen ◽  
John Tianci Li ◽  
Duy Xuan Luong ◽  
...  
Keyword(s):  
Transition Metal ◽  
Joule Heating ◽  
High Performance ◽  
Low Cost ◽  
Transition Metal Carbide ◽  
Heating Process ◽  
Metal Carbides ◽  
Carbide Phases ◽  
Molybdenum Carbides ◽  
Phase Engineering

AbstractNanoscale carbides enhance ultra-strong ceramics and show activity as high-performance catalysts. Traditional lengthy carburization methods for carbide syntheses usually result in coked surface, large particle size, and uncontrolled phase. Here, a flash Joule heating process is developed for ultrafast synthesis of carbide nanocrystals within 1 s. Various interstitial transition metal carbides (TiC, ZrC, HfC, VC, NbC, TaC, Cr2C3, MoC, and W2C) and covalent carbides (B4C and SiC) are produced using low-cost precursors. By controlling pulse voltages, phase-pure molybdenum carbides including β-Mo2C and metastable α-MoC1-x and η-MoC1-x are selectively synthesized, demonstrating the excellent phase engineering ability of the flash Joule heating by broadly tunable energy input that can exceed 3000 K coupled with kinetically controlled ultrafast cooling (>104 K s−1). Theoretical calculation reveals carbon vacancies as the driving factor for topotactic transition of carbide phases. The phase-dependent hydrogen evolution capability of molybdenum carbides is investigated with β-Mo2C showing the best performance.

scholarly journals Predicting the Effect of Dopants on CO2 Adsorption on Transition Metal Carbides: Case Study on TiC (001)

2020 ◽  
Author(s):  
Marti Lopez ◽  
Francesc Vines ◽  
Michael Nolan ◽  
Frances Illas
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Density Functional ◽  
Transition Metal Carbide ◽  
Metal Carbides ◽  
Functional Theory ◽  
Late Transition Metals ◽  
Late Transition ◽  
Early Transition

Previous work has shown that doping the TiC(001) surface with early transition metals significantly affects CO<sub>2</sub> adsorption and activation which opens a possible way to control this interesting chemistry. In this work we explore other possibilities which include non-transition metals elements (Mg, Ca, Sr, Al, Ga, In, Si, Sn) as well as late transition metals (Pd, Pt, Rh, Ir) and lanthanides (La, Ce) often used in catalysis. Using periodic slab models with large supercells and state-of-the-art density functional theory (DFT) based calculations, we show that, in all the studied cases, CO<sub>2</sub> appears as bent and, hence, activated. However, the effect is especially pronounced for dopants with large ionic crystal radii. These can increase desorption temperature by up to 230K, almost twice the value predicted when early transition metals are used as dopants. However, a detailed analysis of the results shows that the main effect does not come from electronic structure perturbations but from the distortion that the dopant generates into the surface atomic structure. A simple descriptor is proposed that would allow predicting the effect of the dopant on the CO<sub>2</sub> adsorption energy in transition metal carbide surfaces without requiring DFT calculations.

Catalytic deoxygenation on transition metal carbide catalysts

2016 ◽  
Vol 6 (3) ◽  
pp. 602-616 ◽  
Author(s):  
Mark M. Sullivan ◽  
Cha-Jung Chen ◽  
Aditya Bhan
Keyword(s):  
Transition Metal ◽  
Transition Metal Carbide ◽  
Metal Carbide ◽  
Metal Carbides ◽  
Transition Metal Carbides ◽  
Catalytic Function ◽  
Catalytic Deoxygenation ◽  
Selective Deoxygenation

We highlight the evolution and tunability of catalytic function of transition metal carbides under oxidative and reductive environments for selective deoxygenation reactions.

scholarly journals Predicting the Effect of Dopants on CO2 Adsorption on Transition Metal Carbides: Case Study on TiC (001)

2020 ◽  
Author(s):  
Marti Lopez ◽  
Francesc Vines ◽  
Michael Nolan ◽  
Frances Illas
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Density Functional ◽  
Transition Metal Carbide ◽  
Metal Carbides ◽  
Functional Theory ◽  
Late Transition Metals ◽  
Late Transition ◽  
Early Transition

Previous work has shown that doping the TiC(001) surface with early transition metals significantly affects CO<sub>2</sub> adsorption and activation which opens a possible way to control this interesting chemistry. In this work we explore other possibilities which include non-transition metals elements (Mg, Ca, Sr, Al, Ga, In, Si, Sn) as well as late transition metals (Pd, Pt, Rh, Ir) and lanthanides (La, Ce) often used in catalysis. Using periodic slab models with large supercells and state-of-the-art density functional theory (DFT) based calculations, we show that, in all the studied cases, CO<sub>2</sub> appears as bent and, hence, activated. However, the effect is especially pronounced for dopants with large ionic crystal radii. These can increase desorption temperature by up to 230K, almost twice the value predicted when early transition metals are used as dopants. However, a detailed analysis of the results shows that the main effect does not come from electronic structure perturbations but from the distortion that the dopant generates into the surface atomic structure. A simple descriptor is proposed that would allow predicting the effect of the dopant on the CO<sub>2</sub> adsorption energy in transition metal carbide surfaces without requiring DFT calculations.

Transition metal carbide-based materials: synthesis and applications in electrochemical energy storage

2016 ◽  
Vol 4 (27) ◽  
pp. 10379-10393 ◽  
Author(s):  
Ying Xiao ◽  
Jang-Yeon Hwang ◽  
Yang-Kook Sun
Keyword(s):  
Transition Metal ◽  
Electrochemical Energy Storage ◽  
Transition Metal Carbide ◽  
Metal Carbide ◽  
Metal Carbides ◽  
Materials Synthesis ◽  
High Chemical ◽  
Transition Metal Carbides ◽  
The Past ◽  
High Chemical Stability

Transition metal carbides have attracted vast interest over the past years due to their appealing properties such as high conductivity, high chemical stability and thermal stability.

Stabilizing polysulfide-shuttle in a Li–S battery using transition metal carbide nanostructures

RSC Advances ◽  
2016 ◽  
Vol 6 (111) ◽  
pp. 110301-110306 ◽  
Author(s):  
Hesham Al Salem ◽  
Venkateswara Rao Chitturi ◽  
Ganguli Babu ◽  
Juan A. Santana ◽  
Deepesh Gopalakrishnan ◽  
...  
Keyword(s):  
Transition Metal ◽  
Transition Metal Carbide ◽  
Metal Carbide ◽  
Metal Carbides ◽  
Practical Applications ◽  
Polysulfide Shuttle

Metal carbides nanostrcutures to stabilize polysulfide shuttle which is a key bottleneck for practical applications of Li–S battery.

Titanium Carbide from Carboxylic Acid Modified Alkoxides

1992 ◽  
Vol 271 ◽  
Author(s):  
Tom Gallo ◽  
Carl Greco ◽  
Claude Peterson ◽  
Frank Cambria ◽  
Johst Burk
Keyword(s):  
Transition Metal ◽  
Carbon Content ◽  
Polymeric Materials ◽  
Dicarboxylic Acids ◽  
Transition Metal Carbide ◽  
Metal Carbide ◽  
Metal Carbides ◽  
X Ray Diffraction ◽  
Increase Carbon Content ◽  
Reducing Conditions

ABSTRACTTransition metal carbide precursors have been made in the past by the reaction of alkoxides with polymeric materials to form gels and resins. A new route to transition metal carbide precursors has been developed using alkoxides polymerized with dicarboxylic acids. (Dicarboxylic acid precursors have the advantage of precipitating as powders that can be removed from solvents by filtration and that are not very air sensitive.) Precursors were pyrolyzed under inert or reducing conditions to form metal carbides.The choice of ligand(s) determined the carbon content after pyrolysis. Unsaturated ligands tended to increase carbon content. Materials from oils to fine powders were produced by varying the stereochemistry of the ligands. The morphology of the pyrolyzed product mimicked that of the precipitated powder. Pyrolysis was typically carried out under Ar/H2 at 1200–1600°C. X-ray diffraction (XRD) was used to follow the incorporation of carbon into the lattice.

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