An identification of the soft polyelectrolyte gel-like layer on silica colloids using atomic force and electron microscopy

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F17%3A10368161" target="_blank" >RIV/00216208:11310/17:10368161 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1016/j.ultramic.2017.05.011" target="_blank" >https://doi.org/10.1016/j.ultramic.2017.05.011</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ultramic.2017.05.011" target="_blank" >10.1016/j.ultramic.2017.05.011</a>

Jazyk výsledku

angličtina

Název v původním jazyce

An identification of the soft polyelectrolyte gel-like layer on silica colloids using atomic force and electron microscopy

Popis výsledku v původním jazyce

A procedure is introduced for measuring the radius of spherical colloid particles from the curvature of upper parts of their central cross-sectional profiles obtained by atomic force microscopy (AFM). To minimize the possible compression and displacement of the spheres, AFM is operated in a mode rendering a constant ultralow pN force on the tip. The procedure allows us to evaluate the mean radius of nearly monodisperse submicrometer spheres of silica in their natively hydrated state in aqueous electrolyte solutions, irrespective of whether they are coagulated or not. A variation in the volume (swelling degree) of layers delimited by the AFM mean radii of these spheres in KCl solutions and their invariable mean radius in vacuum is obtained that follows a scaling power law derived in polymer physics for swellable polyelectrolyte gels and deduced previously by us from coagulation tests. This supports &apos;our former suggestion about the existence of soft polyelectrolyte gel-like-layer developed spontaneously around silica surfaces and colloids. We discuss this finding in the context of recent knowledge about the structure of the silica/water interface obtained from direct surface force measurements between macroscopic silica surfaces and from particle size measurements of silica colloids and highlight its importance for colloid chemistry and condensed mattter physics.

Název v anglickém jazyce

An identification of the soft polyelectrolyte gel-like layer on silica colloids using atomic force and electron microscopy

Popis výsledku anglicky

A procedure is introduced for measuring the radius of spherical colloid particles from the curvature of upper parts of their central cross-sectional profiles obtained by atomic force microscopy (AFM). To minimize the possible compression and displacement of the spheres, AFM is operated in a mode rendering a constant ultralow pN force on the tip. The procedure allows us to evaluate the mean radius of nearly monodisperse submicrometer spheres of silica in their natively hydrated state in aqueous electrolyte solutions, irrespective of whether they are coagulated or not. A variation in the volume (swelling degree) of layers delimited by the AFM mean radii of these spheres in KCl solutions and their invariable mean radius in vacuum is obtained that follows a scaling power law derived in polymer physics for swellable polyelectrolyte gels and deduced previously by us from coagulation tests. This supports &apos;our former suggestion about the existence of soft polyelectrolyte gel-like-layer developed spontaneously around silica surfaces and colloids. We discuss this finding in the context of recent knowledge about the structure of the silica/water interface obtained from direct surface force measurements between macroscopic silica surfaces and from particle size measurements of silica colloids and highlight its importance for colloid chemistry and condensed mattter physics.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Ultramicroscopy

ISSN

0304-3991

e-ISSN

—

Svazek periodika

181

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

10

Strana od-do

97-106

Kód UT WoS článku

000411170800012

EID výsledku v databázi Scopus

2-s2.0-85019480861