Surface properties of sodium, potassium, and their binary alloys in the liquid state

Ашхотов, О. Г.; Ашхотова, И. Б.; Aleroev, M. A.; Магкоев, Т. Т.; Bliev, A. P.

doi:10.1134/s0036024417070032

Cited by 4 publications

(3 citation statements)

References 5 publications

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“…The preferential surface enrichment with Bi is corroborated by our DFT calculations. Similar surface enrichment in one component, namely, the lower-surface-tension component, has been seen for other binary liquid metal alloys. − …”

Section: Experimental Resultssupporting

confidence: 59%

Methane Pyrolysis with a Molten Cu–Bi Alloy Catalyst

et al. 2019

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Current methods of hydrogen production from methane generate more than 5 kg of CO2 for every 1 kg of hydrogen. Methane pyrolysis on conventional solid heterogeneous catalysts produces hydrogen without CO2, but the carbon coproduct poisons the catalyst. This can be avoided by using a molten metal alloy catalyst. We present here a study of methane pyrolysis using mixtures of molten Cu–Bi alloys as the catalyst. We find that molten Cu–Bi is an active catalyst, even though pure molten Bi and Cu are not. Surface tension measurements and constant-temperature ab initio molecular dynamics simulations indicate that the surface is enriched in Bi and that the catalytic activity is correlated with the concentration of Bi at the surface. Bader charge analysis indicates that bismuth donates charge to copper. In the most stable configuration of dissociated methane on these liquid surfaces, CH3 binds to a bismuth surface atom and H to Cu. The energy barriers for the dissociative adsorption of methane, calculated using the nudged elastic band (NEB) method, are between 2.5 and 2.6 eV, depending on the binding site on the surface of the Cu45Bi55 alloy. The computed barriers are in rough agreement with the experimental apparent activation energy of 2.3 eV.

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Section: Experimental Resultssupporting

confidence: 59%

Methane Pyrolysis with a Molten Cu–Bi Alloy Catalyst

et al. 2019

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“…The surface reactions of the ions of these gases with Li were studied using Auger electron spectroscopy. The spectra were obtained using an Auger spectrometer based on the USU-4 [7] ultrahigh vacuum setup. The limiting residual pressure in the chamber of the Auger spectrometer was 5 • 10 −8 Pa.…”

Section: Experimental Partmentioning

confidence: 99%

Investigation of the effect of nitrogen ion irradiation on the lithium surface condition

Ашхотов

Магкоев

Ашхотова

2023

Physics of the Solid State

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A comparison of the surface of solid lithium in the atomically pure state, after contact with oxygen, nitrogen and after irradiation with N+ ions with an energy of 0.6 keV at a current density of 2 μA/mm2 was carried out. The analysis of surface characteristics was carried out using electron Auger spectroscopy. To obtain an atomically pure surface, low-energy electron bombardment was used. It is shown that the contact of an atomically pure Li surface with oxygen leads to the formation of lithium oxide, and with nitrogen with a partial pressure of 10-6 Pa, lithium oxide and oxynitride in a mixture with free lithium atoms. Irradiation of lithium with nitrogen ions leads to the formation of the surface compound Li3N. It is noted that the resulting compound is unstable in ultrahigh vacuum and eventually decays to form lithium oxide due to interaction with the residual oxygen of the spectrometer chamber. Keywords: lithium, vacuum, ions, electrons, surface.

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“…However, different sources report different NaK surface tension values due to the difficulty of measuring procedure. 34 NaK heat capacity is approximately one fourth that of water, but its heat transfer is much higher due to higher thermal conductivity (more than 30 times). Based on various experimental data from different sources, the dependence of NaK density on absolute temperature (K) can be approximated using eqn (2), which was proposed by Chernov et al 35 ρ = 938.40 − (236.92 × 10 3 )/ T …”

Section: What Is the Nak Alloy?mentioning

confidence: 99%