Charged Colloids at the Metal–Electrolyte Interface
We discuss the peculiarities of the structure of the interface between a metal and a stable colloidal dispersion of charged nanoparticles in an electrolyte. It is demonstrated that a quasi-2D ionic structure of elevated density arises in its vicinity due to the effect of electrostatic image forces....
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-04-01
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| Series: | Colloids and Interfaces |
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| Online Access: | https://www.mdpi.com/2504-5377/6/2/25 |
| _version_ | 1827661200251420672 |
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| author | Ioulia Chikina Sawako Nakamae Valeriy Shikin Andrey Varlamov |
| author_facet | Ioulia Chikina Sawako Nakamae Valeriy Shikin Andrey Varlamov |
| author_sort | Ioulia Chikina |
| collection | DOAJ |
| description | We discuss the peculiarities of the structure of the interface between a metal and a stable colloidal dispersion of charged nanoparticles in an electrolyte. It is demonstrated that a quasi-2D ionic structure of elevated density arises in its vicinity due to the effect of electrostatic image forces. The stabilized colloidal particles, being electroneutral and spatially distributed objects in the bulk of the electrolyte and approaching the interface, are attracted to it. In their turn, the counterions forming their coat partially retract into the 2D-layer, which results in an acquisition by the colloidal particle of the effective charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><msup><mi>Z</mi><mo>*</mo></msup><mo>≫</mo><mi>e</mi></mrow></semantics></math></inline-formula> and which, together with its mirror image, creates the electric dipole. The formed dipoles, possessing the moments directed perpendicularly to the interface, form the gas with repulsion between particles. The intensity of this repulsion, evidently, depends on the value of the effective charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><msup><mi>Z</mi><mo>*</mo></msup></mrow></semantics></math></inline-formula> acquired by the nanoparticle having lost a number of counterions. It can be related to the value of the excess osmotic pressure <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>P</mi><mrow><mi>o</mi><mi>s</mi><mi>m</mi></mrow></msub></semantics></math></inline-formula> measured in the experiment. On the other hand, this effective charge can be connected by means of the simple geometric consideration with the structural charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><mi>Z</mi></mrow></semantics></math></inline-formula> of the nanoparticle core being in the bulk of the electrolyte. |
| first_indexed | 2024-03-10T00:05:10Z |
| format | Article |
| id | doaj.art-42b21eab91f248ec94f378b7bff8259f |
| institution | Directory Open Access Journal |
| issn | 2504-5377 |
| language | English |
| last_indexed | 2024-03-10T00:05:10Z |
| publishDate | 2022-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Colloids and Interfaces |
| spelling | doaj.art-42b21eab91f248ec94f378b7bff8259f2023-11-23T16:09:12ZengMDPI AGColloids and Interfaces2504-53772022-04-01622510.3390/colloids6020025Charged Colloids at the Metal–Electrolyte InterfaceIoulia Chikina0Sawako Nakamae1Valeriy Shikin2Andrey Varlamov3LIONS, NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, FranceService de Physique de L‘etat Condensé, SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, FranceMediterranean Institute of Fundamental Physics, Via Appia Nuova 31, 00047 Marino, ItalyCNR-SPIN, Via del Fosso del Cavaliere 100, 00133 Rome, ItalyWe discuss the peculiarities of the structure of the interface between a metal and a stable colloidal dispersion of charged nanoparticles in an electrolyte. It is demonstrated that a quasi-2D ionic structure of elevated density arises in its vicinity due to the effect of electrostatic image forces. The stabilized colloidal particles, being electroneutral and spatially distributed objects in the bulk of the electrolyte and approaching the interface, are attracted to it. In their turn, the counterions forming their coat partially retract into the 2D-layer, which results in an acquisition by the colloidal particle of the effective charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><msup><mi>Z</mi><mo>*</mo></msup><mo>≫</mo><mi>e</mi></mrow></semantics></math></inline-formula> and which, together with its mirror image, creates the electric dipole. The formed dipoles, possessing the moments directed perpendicularly to the interface, form the gas with repulsion between particles. The intensity of this repulsion, evidently, depends on the value of the effective charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><msup><mi>Z</mi><mo>*</mo></msup></mrow></semantics></math></inline-formula> acquired by the nanoparticle having lost a number of counterions. It can be related to the value of the excess osmotic pressure <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>P</mi><mrow><mi>o</mi><mi>s</mi><mi>m</mi></mrow></msub></semantics></math></inline-formula> measured in the experiment. On the other hand, this effective charge can be connected by means of the simple geometric consideration with the structural charge <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>e</mi><mi>Z</mi></mrow></semantics></math></inline-formula> of the nanoparticle core being in the bulk of the electrolyte.https://www.mdpi.com/2504-5377/6/2/25seebeck effectcolloidsthermodiffusion |
| spellingShingle | Ioulia Chikina Sawako Nakamae Valeriy Shikin Andrey Varlamov Charged Colloids at the Metal–Electrolyte Interface Colloids and Interfaces seebeck effect colloids thermodiffusion |
| title | Charged Colloids at the Metal–Electrolyte Interface |
| title_full | Charged Colloids at the Metal–Electrolyte Interface |
| title_fullStr | Charged Colloids at the Metal–Electrolyte Interface |
| title_full_unstemmed | Charged Colloids at the Metal–Electrolyte Interface |
| title_short | Charged Colloids at the Metal–Electrolyte Interface |
| title_sort | charged colloids at the metal electrolyte interface |
| topic | seebeck effect colloids thermodiffusion |
| url | https://www.mdpi.com/2504-5377/6/2/25 |
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