Forces between silica particles in the presence of multivalent cations

Article Article scientifique Article Forces between silica particles in the presence of multivalent cations eng 2016 author Valmacco Valentina 765249 author Elzbieciak-Wodka Magdalena author Herman David Joël 841035 author Trefalt Gregor 786132 author Maroni Plinio 644101 author Borkovec Michal 134121 108-115 10.1016/j.jcis.2016.03.043 0021-9797 http://linkinghub.elsevier.com/retrieve/pii/S0021979716301850 Forces between negatively charged silica particles in aqueous electrolyte solutions were measured with the colloidal probe technique based on the atomic force microscope (AFM). The present study focuses on the comparison of monovalent and multivalent counterions, namely K+, Mg2+, and La3+. The force profiles can be well described with the theory of Derjaguin, Landau, Verwey, and Overbeek (DLVO) down to distances of about 4 nm. At smaller distances, the forces become strongly repulsive due to additional non-DLVO repulsion. In the presence of La3+, one observes an additional attractive force with a range of about 1 nm at intermediate salt concentrations. This force is probably related to ion-ion correlations, but could also be influenced by surface charge heterogeneities or charge fluctuation forces. Atomic force microscope Colloidal probe technique Direct force measurement Water-silica interface Multivalent ion Dewey 540 40 Département de chimie minérale, analytique et appliquée 145 false 773 Groupe Borkovec Journal of Colloid and Interface Science 472 bb4e74e4-799a-40c0-99ac-d885146b6de6 Article (Published version) Restricted 1-s2.0-S0021979716301850-main.pdf 1289558 application/pdf restrictedAccess Faculté des sciences / Section de chimie et biochimie / Département de chimie minérale, analytique et appliquée

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Forces between silica particles in the presence of multivalent cations	Journal of Colloid and Interface Science			2016	471	0

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Herman, David Joël