title: Time-resolved microfocused small-angle X-ray scattering investigation of the microfluidic concentration of charged nanoparticles.
abstract: We describe the concentration process of a dispersion of silica nanoparticles undergoing evaporation in a dedicated microfluidic device. Using microfocused small-angle X-ray scattering, we measure in time and space both the concentration field of the dispersion and its structure factor. We show that the electrostatic interactions affect the concentration rate by strongly enhancing the collective diffusion coefficient of the nanoparticle dispersion. En route towards high concentrations, the nanoparticles eventually undergo a liquid-solid phase transition in which we evidence crystallites of micron size.
authors.affiliation: UMR Rhodia-CNRS-Bordeaux, Pessac cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Merlin
authors.forename: J
authors.initials: J
authors.lastname: Angly
authors.forename: L
authors.initials: L
authors.lastname: Daubersies
authors.forename: C
authors.initials: C
authors.lastname: Madeira
authors.forename: S
authors.initials: S
authors.lastname: Schöder
authors.forename: J
authors.initials: J
authors.lastname: Leng
authors.forename: J-B
authors.initials: JB
authors.lastname: Salmon
mesh_terms: D000465:Algorithms; D004058:Diffusion; D004867:Equipment Design / Q000295:instrumentation*; D046210:Microfluidic Analytical Techniques / Q000379:methods; D044085:Microfluidics / Q000295:instrumentation*; D053758:Nanoparticles / Q000737:chemistry*; D044367:Phase Transition; D053838:Scattering, Small Angle; D012822:Silicon Dioxide / Q000737:chemistry*; D013997:Time Factors; D014961:X-Ray Diffraction / Q000379:methods*; D014965:X-Rays
chemical_list: D012822:Silicon Dioxide