New Design of a Sample Cell for Neutron Reflectometry in Liquid-Liquid Systems and Its Application for Studying Structures at Air-Liquid and Liquid-Liquid Interfaces

Knowledge of interfacial structures in liquid-liquid systems is imperative, especially for improving two-phase biological and chemical reactions. Therefore, we developed a new sample cell for neutron reflectometry (NR), which enables us to observe the layer structure around the interface, and investigated the adsorption behavior of a typical surfactant, sodium dodecyl sulfate (SDS), on the toluene-d(8)-D2O interface under the new experimental conditions. The new cell was characterized by placing the PTFE frame at the bottom to produce a smooth interface and downsized compared to the conventional cell. The obtained NR profiles were readily analyzable and we determined a slight difference in the SDS adsorption layer structure at the interface between the toluene-d(8)-D2O and air-D2O systems. This could be owing to the difference in the adsorption behavior of the SDS molecules depending on the interfacial conditions.

Automated summary

Knowledge of interfacial structures in liquid-liquid systems is crucial for enhancing two-phase biological and chemical reactions. A new sample cell for neutron reflectometry (NR) was developed to observe the layer structure around the interface. The adsorption behavior of SDS on the toluene-D2O interface was investigated under the new experimental conditions.