Interfacial Activity of AuC6 Nanoparticles Using the Pendant Drop Technique

The structure and orientation of nanoparticles at the liquid–liquid interface may be useful for the preparation of robust, self-assembled structures, devices, and membranes. The pendant drop technique enables to study the interfacial activity of nanoparticles with smaller amounts and upon more controlled conditions than with the traditional Langmuir film balance technique. The pendant drop technique was applied to characterize the interfacial activity of 2 nm-diameter AuC6 nanoparticles. The AuC6 nanoparticles in tetrahydrofuran solution deposited at the water/air interface described a violent adsorption process as the tetrahydrofuran was evaporated. Growing and shrinking experiments for the water/air and water/decane interfaces enabled to explore the arrangement of the AuC6 nanoparticles at each interface. A simply scaled particle theory of hard disks model was in agreement with the experimental data.