Dynamically engineering the interfacial interaction of nanoparticles has emerged as a new approach for bottom‐up fabrication of smart systems to tailor molecular diffusion and controlled release. Janus zwitterionic nanoplates are reported that can be switched between a locked and unlocked state at interfaces upon changing surface charge, allowing manipulation of interfacial properties in a fast, flexible, and switchable manner. Combining experimental and modeling studies, an unambiguous correlation is established among the electrostatic energy, the interface geometry, and the interfacial jamming states. As a proof‐of‐concept, the well‐controlled interfacial jamming of nanoplates enabled the switchable molecular diffusion through liquid–liquid interfaces, confirming the feasibility of using nanoparticle‐based surfactants for advanced controlled release.