Surface Characterization of Colloidal Silica Nanoparticles by Second Harmonic Scattering: Quantifying the Surface Potential and Interfacial Water Order.

ABSTRACT: 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.

SUBMITTER: Marchioro A 

PROVIDER: S-EPMC9182216 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature