Surface Characterization of Colloidal Silica Nanoparticles by Second Harmonic Scattering: Quantifying the Surface Potential and Interfacial Water Order
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60076658%3A12310%2F19%3A43899381" target="_blank" >RIV/60076658:12310/19:43899381 - isvavai.cz</a>
Result on the web
<a href="https://pubs.acs.org/doi/pdf/10.1021/acs.jpcc.9b05482" target="_blank" >https://pubs.acs.org/doi/pdf/10.1021/acs.jpcc.9b05482</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acs.jpcc.9b05482" target="_blank" >10.1021/acs.jpcc.9b05482</a>
Alternative languages
Result language
angličtina
Original language name
Surface Characterization of Colloidal Silica Nanoparticles by Second Harmonic Scattering: Quantifying the Surface Potential and Interfacial Water Order
Original language description
The microscopic description of the interface of colloidal particles in solution is essential to understand and predict the stability of these systems, as well as their chemical and electrochemical reactivity. However, this description often relies on the use of simplified electrostatic mean field models for the structure of the interface, which give only theoretical estimates of surface potential values and do not provide properties related to the local microscopic structure, such as the orientation of interfacial water molecules. Here we apply polarimetric angle-resolved second harmonic scattering (AR-SHS) to 300 nm diameter SiO2 colloidal suspensions to experimentally determine both surface potential and interfacial water orientation as a function of pH and NaCl concentration. The surface potential values and interfacial water orientation change significantly over the studied pH and salt concentration range, whereas zeta-potential (zeta) values remain constant. By comparing the surface and zeta-potentials, we find a layer of hydrated condensed ions present in the high pH case, and for NaCl concentrations >= 1 mM. For milder pH ranges (pH < 11), as well as for salt concentrations <1 mM, no charge condensation layer is observed. These findings are used to compute the surface charge densities using the Gouy-Chapman and Gouy-Chapman-Stern models. Furthermore, by using the AR-SHS data, we are able to determine the preferred water orientation in the layer directly in contact with the silica interface. Molecular dynamics simulations confirm the experimental trends and allow deciphering of the contributions of water layers to the total response.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
20501 - Materials engineering
Result continuities
Project
<a href="/en/project/GA17-10734S" target="_blank" >GA17-10734S: Molecular description of phenomena in electrical double layer - prediction and interpretation of experimental data by computer simulations</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2019
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of Physical Chemistry C
ISSN
1932-7447
e-ISSN
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Volume of the periodical
123
Issue of the periodical within the volume
33
Country of publishing house
US - UNITED STATES
Number of pages
12
Pages from-to
20393-20404
UT code for WoS article
000482545700036
EID of the result in the Scopus database
2-s2.0-85071680594