Amphiphilic Janus nanoparticles exhibit higher interfacial activity and adsorb more strongly to fluid interfaces than homogeneous nanoparticles of similar sizes. Taking advantage of both shape and chemical anisotropy on the same particle, Janus particles offer rich self-assembly possibilities for nanotechnology. By using dissipative particle dynamics simulation, the translational diffusion of Janus nanoparticles at the interface between two immiscible fluids is investigated. The particle aspect ratio affects both particle's translational thermal motion and the average orientation of the particle with respect to the interface at equilibrium. This behavior is also linked to the interfacial tension of the system. Our findings provide fundamental insights into the dynamics and self-assembly of anisotropic Brownian particles at interfaces.

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