The effect of method of preparation on the catalytic activity of tungsten carbide

Nikolov, I.; Nikolova, V.; Vitanov, T.; Svatá, M.

doi:10.1016/0378-7753(79)80038-5

Cited by 23 publications

(4 citation statements)

References 10 publications

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“…Nikolov et al proposed that the starting materials, and the carburization atmosphere, do not influence the activity of tungsten carbide. 14,15 The catalytic activity of tungsten carbide was defined only as a function of the specific surface area. 15 The differences in catalytic activities of tungsten carbides result from differences in surface properties, such as particle morphology and the chemical composition of the surface layer, which could be significantly different from the bulk.…”

Section: Introductionmentioning

confidence: 99%

“…Nikolov et al proposed that the starting materials, and the carburization atmosphere, do not influence the activity of tungsten carbide. , The catalytic activity of tungsten carbide was defined only as a function of the specific surface area , Particle morphology was shown to have a strong influence on electrocatalytic properties of tungsten carbide catalysts .…”

Section: Introductionmentioning

confidence: 99%

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Preparation and Formation Mechanism of Hollow Microspherical Tungsten Carbide with Mesoporosity

Brandon

2007

J. Phys. Chem. C

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Hollow microspherical tungsten carbide with mesoporosity was prepared by spray-drying sphere miniaturization/gas−solid reaction, using ammonium metatungstate (AMT) as a precursor, carbon monoxide as a reducing gas, and carbon dioxide as a carrier gas. The samples were characterized by XRD, SEM, and EDS. XRD and EDS results show that the samples are phase pure WC, with a ratio of W/C ≈ 1. SEM results show that the hollow microsphere forms during spray-drying sphere miniaturization, and mesoporosity forms by gas−solid reaction during subsequent heat treatment. To investigate the phase transition during the gas−solid reaction, the samples were monitored by in situ XRD in an Anton Paar XRX900 container. The in situ XRD results show that when the reaction temperature is raised to 1023 K slowly and continuously, the phase transition of the sample follows the pattern AMT → WO3 → WO2 → W2C → WC, but when the reaction temperature is raised to 673 K slowly and then raised to 1023 K quickly, the phase transition of the sample follows AMT → WO3 → WO2 → WC. These results indicate that the phase transition of the sample during the heat treatment step is connected to the temperature and the time of the reaction, as well as the rate of the temperature rise.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Preparation and Formation Mechanism of Hollow Microspherical Tungsten Carbide with Mesoporosity

Brandon

2007

J. Phys. Chem. C

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“…Nonetheless, as the availability of nitride and carbide nanostructures is still very restricted and their synthesis is full of potential complications, further developments are necessary for the high stake of replacing noble metals by metal carbides. Above all, catalytic activity may be increased by increasing the specific surface area (producing them in form of small nanoparticles) as well as providing the structure with higher purity and more defined surface structures. , Such well-defined nitride/carbide nanoparticle may have, beside catalysis, additional applications in fields such as biomedicine, electronics and semiconductor devices, and high performance mechanics. Compared to the potentialities of those fields, the number of metal nitride (MN) and metal carbide (MC) nanoparticle syntheses is indeed rather sparse.…”

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confidence: 99%

Synthesis of Mo and W Carbide and Nitride Nanoparticles via a Simple “Urea Glass” Route

et al. 2008

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A simple, inexpensive, and versatile route for the synthesis of metal nitrides and carbides (such as Mo2N, Mo2C, W2N and WC) nanoparticles was set up. For the first time, metal carbides were obtained using urea as carbon-source. MoCl5 and WCl4 are in a first step contacted with alcohols and an appropriate amount of urea to form a polymer-like, glassy phase, which acts as the starting product for further conversions. Just by heating this phase it was possible to prepare either molybdenum and tungsten nitrides or carbides simply by changing the metal precursor/urea molar ratio. In this procedure, urea plays a double role as a nitrogen/carbon source and stabilizing agent (necessary for the nanoparticle dispersion). Molybdenum and tungsten nitride and carbides synthesized are almost pure and highly crystalline. Sizes estimated by WAXS range around 20 and 4 nm in diameter for Mo and W nitrides or carbides, respectively. The specific surface area was found between 10 and 80 m2/g, depending on the metal and the initial ratio of metal precursor to urea.

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“…Tungsten carbide (WC) is widely regarded as one of the potential electrocatalysts for HER owing to its Pt‐like d‐band electronic structure, high electrical conductivity, and high catalytic stability. [ 13–16 ] Unfortunately, however, the relatively strong hydrogen binding on WC severely retards the H 2 desorption step during HER, especially in alkali media, resulting in limited intrinsic catalytic activity. [ 17,18 ] It has been reported that late transition metals (e.g., Fe, Co, and Ni) possessing internally paired d‐electrons into early transition metals (e.g., W and Mo) featuring half‐filled vacant d‐orbitals can be introduced to optimize the electronic structure of WC, and thus, elevate the HER catalytic activity due to the “3d electron complementary effect.” [ 19–21 ] Wang et al.…”

Section: Introductionmentioning

confidence: 99%

CoW Bimetallic Carbide Nanocatalysts: Computational Exploration, Confined Disassembly–Assembly Synthesis and Alkaline/Seawater Hydrogen Evolution

Meng

Chen

Wang

et al. 2022

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Earth‐abundant tungsten carbide exhibits potential hydrogen evolution reaction (HER) catalytic activity owing to its Pt‐like d‐band electronic structure, which, unfortunately, suffers from the relatively strong tungsten‐hydrogen binding, deteriorating its HER performance. Herein, a catalyst design concept of incorporating late transition metal into early transition metal carbide is proposed for regulating the metal–H bonding strength and largely enhancing the HER performance, which is employed to synthesize CoW bi‐metallic carbide Co6W6C by a “disassembly–assembly” approach in a confined environment. Such synthesized Co6W6C nanocatalyst features the optimal Gibbs free energy of *H intermediate and dissociation barrier energy of H2O molecules as well by taking advantage of the electron complementary effect between Co and W species, which endows the electrocatalyst with excellent HER performance in both alkaline and seawater/alkaline electrolytes featuring especially low overpotentials, elevated current densities, and much‐enhanced operation durability in comparison to commercial Pt/C catalyst. Moreover, a proof‐of‐concept Mg/seawater battery equipped with Co6W6C‐2‐600 as cathode offers a peak power density of 9.1 mW cm−2 and an open‐circuit voltage of ≈1.71 V, concurrently realizing hydrogen production and electricity output.

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The effect of method of preparation on the catalytic activity of tungsten carbide

Cited by 23 publications

References 10 publications

Preparation and Formation Mechanism of Hollow Microspherical Tungsten Carbide with Mesoporosity

Preparation and Formation Mechanism of Hollow Microspherical Tungsten Carbide with Mesoporosity

Synthesis of Mo and W Carbide and Nitride Nanoparticles via a Simple “Urea Glass” Route

CoW Bimetallic Carbide Nanocatalysts: Computational Exploration, Confined Disassembly–Assembly Synthesis and Alkaline/Seawater Hydrogen Evolution

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