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Updated: Jan 6, 2026

Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
Surface tension anomaly observed for chemically-modified Janus particles at the air/water interface
Sepideh Razavi1, Laura M Hernandez2, Alismari Read3
1Chemical, Biological, and Materials Engineering, University of Oklahoma, Norman, OK 73019, USA.
Abstract:
The behavior of Janus particles fabricated from core silica particles decorated with gold nanoparticles on one hemisphere is studied at the air/water interface. An unexpected reduction in the effective surface tension is observed in the presence of these chemically-modified Janus particles. Experiments on the interfacial behavior of a variety of control particles, including the physically-modified Janus particles made from the same core silica particles coated with a thin gold layer, do not exhibit significant surface tension effects. We hypothesize that the chemical modification of particles in form of a Janus structure is needed to alter the surface tension and attribute the surfactant-like behavior of these particles to the presence of immersion forces.
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