We investigate active interfacial ion flux in droplet electrohydrodynamics with an emphasis on deformation, pinch-off, and recoalescence. A thermodynamically consistent phase-field framework is developed that couples Nernst–Planck–Poisson electrodiffusion with incompressible Navier–Stokes–Cahn–Hilliard flow and incorporates active interfacial ionic fluxes. In a baseline case without active interfacial transport, applied fields merely polarize the droplet, and deformation is negligible. In contrast, surface-localized active transport drives the accumulation of positive ions within the droplet, elevates the interior potential, and generates nonuniform electric fields. The resulting electric stresses stretch and displace the droplet, thin interfacial necks, and trigger pinch-off; the daughter droplets subsequently recoalesce, often after wall contact, yielding flattened remnants. In multiple-droplet configurations, charging induced by active interfacial transport produces lateral electrostatic repulsion and asymmetric deformation; under geometric confinement, crescent bending and star-like morphologies emerge. Poiseuille-flow tests further show that a droplet with active transport can be immobilized and ruptured, while a neighbor without active flux is advected downstream, suggesting a route to sorting. Together, the results establish active interfacial transport as an internal actuation mechanism that robustly controls droplet morphology and dynamics across configurations.

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