Aerosol Flow Reactor with Controlled Temperature Gradient for In Situ Gas-Phase X-Ray Experiments—Measurements of Evaporation-Induced Self-Assembly (EISA) in Aerosols

Abstract

We present a new in situ aerosol flow reactor for gas-phase studies during drying of aerosol droplets by small-angle X-ray scattering (SAXS). The setup consists of an outer confinement shell and an inner tube for aerosol flow that can be positioned by a remote-controlled motor to perform scanning measurements along the flow path, providing “quasi-time-resolved” information on the drying process. A controlled temperature step is provided by an insulating separation between a cooled and a heated section in the dryer. First experiments were performed on aerosols of surfactant- and silica-precursor/surfactant solutions (CTAB/ethanol, TEOS/CTAB). Measurements of the mesostructure formation during the initial steps of evaporation-induced self-assembly (EISA) were made to illustrate the working principle of aerosol drying during passage through an adjustable temperature gradient.

Acknowledgments

We thank Christian Morello for his support with the setup. The study was financed by the project SAXIER contract no. RIDS 011934.

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