Molecular dynamics of the interfacial solution structure of alkali-halide electrolytes at graphene electrodes.
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F22%3A00554860" target="_blank" >RIV/67985858:_____/22:00554860 - isvavai.cz</a>
Nalezeny alternativní kódy
RIV/44555601:13440/22:43897043
Výsledek na webu
<a href="http://hdl.handle.net/11104/0329486" target="_blank" >http://hdl.handle.net/11104/0329486</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.molliq.2022.118776" target="_blank" >10.1016/j.molliq.2022.118776</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Molecular dynamics of the interfacial solution structure of alkali-halide electrolytes at graphene electrodes.
Popis výsledku v původním jazyce
In this paper, we have studied structural changes in several prototypical aqueous solutions of electrolytes (NaCl, KCl, and LiCl) in contact with graphene induced by its either positive or negative electric charge, under ambient conditions. We have carried out molecular-dynamics simulations using the most accurate interaction models available. We have analysed the solution structure using an advanced analysis of the intermolecular bonding, and also standard properties such as density and charge density profiles, electrostatic potential, and screening functions. Our results show that the graphene charge has nearly no translational effect on water molecules, whereas it significantly changes their orientations, and the effect on ions’ distributions differ from solution to solution. Larger ions, whose hydration shells are weaker, are affected directly in an intuitive fashion, i.e., cations are attracted by negatively charged graphene and vice versa, whereas effects on smaller ions may vary and may be even counterintuitive, e.g., the number of chlorine anions in aqueous KCl in contact with negatively charged graphene is greater when compared to neutral graphene. The surplus of chlorine anions adsorbed on a positively charged electrode strengthens the structure of water and counterintutitively rotates the water molecules in the second layer pointing their electric dipoles preferentially to the electrode. The surplus of cations due to a negatively charged electrode is accompanied by a weakening of the water structure in the case of larger ions, whereas in the case of the lithium cation the structure is stronger due to the direct effects of the graphene charge on water molecules. Regardless of the graphene charge, the total number of intermolecular bonds connected with a single water molecule is nearly independent of the distance from the graphene surface and the same applies to the number of intermolecular bonds connected with a single ion, which means that whenever a particle loses an intermolecular bond it nearly always forms a new bond as a compensation.
Název v anglickém jazyce
Molecular dynamics of the interfacial solution structure of alkali-halide electrolytes at graphene electrodes.
Popis výsledku anglicky
In this paper, we have studied structural changes in several prototypical aqueous solutions of electrolytes (NaCl, KCl, and LiCl) in contact with graphene induced by its either positive or negative electric charge, under ambient conditions. We have carried out molecular-dynamics simulations using the most accurate interaction models available. We have analysed the solution structure using an advanced analysis of the intermolecular bonding, and also standard properties such as density and charge density profiles, electrostatic potential, and screening functions. Our results show that the graphene charge has nearly no translational effect on water molecules, whereas it significantly changes their orientations, and the effect on ions’ distributions differ from solution to solution. Larger ions, whose hydration shells are weaker, are affected directly in an intuitive fashion, i.e., cations are attracted by negatively charged graphene and vice versa, whereas effects on smaller ions may vary and may be even counterintuitive, e.g., the number of chlorine anions in aqueous KCl in contact with negatively charged graphene is greater when compared to neutral graphene. The surplus of chlorine anions adsorbed on a positively charged electrode strengthens the structure of water and counterintutitively rotates the water molecules in the second layer pointing their electric dipoles preferentially to the electrode. The surplus of cations due to a negatively charged electrode is accompanied by a weakening of the water structure in the case of larger ions, whereas in the case of the lithium cation the structure is stronger due to the direct effects of the graphene charge on water molecules. Regardless of the graphene charge, the total number of intermolecular bonds connected with a single water molecule is nearly independent of the distance from the graphene surface and the same applies to the number of intermolecular bonds connected with a single ion, which means that whenever a particle loses an intermolecular bond it nearly always forms a new bond as a compensation.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10403 - Physical chemistry
Návaznosti výsledku
Projekt
Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.
Návaznosti
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Ostatní
Rok uplatnění
2022
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
Journal of Molecular Liquids
ISSN
0167-7322
e-ISSN
1873-3166
Svazek periodika
353
Číslo periodika v rámci svazku
1 May
Stát vydavatele periodika
NL - Nizozemsko
Počet stran výsledku
18
Strana od-do
118776
Kód UT WoS článku
000820347200007
EID výsledku v databázi Scopus
2-s2.0-85125624709