We report on the spontaneous formation of nano-sized ionic liquid/water (IL/W) emulsions in a simple system solely composed of an IL and aqueous solution of an inorganic salt. The IL ions play a dual role, that of both a surfactant and the dispersed phase. No extra surfactant is needed to promote emulsification. Droplets generation at the IL/W interface is captured by nanoparticulate and porous films that imprint the morphology of this unstable interface. The emulsion droplets are employed to create core-shell microcrystals with potential functionality.