Controlling the morphology of silver deposition at liquid|liquid interfaces: From nano-wires to super smooth films

Crystals of metallic silver can be grown at liquid|liquid interfaces when the aqueous phase contains silver ions and the organic phase ferrocene or decamethylferrocene. By choosing appropriate concentrations of the reactants in the two phases it is possible to get either the growth of silver wires (whiskers with radii from about 50 nm to 50 μm) growing from the interface into the organic phase, Christmas tree-like deposits at the interface, or even extremely smooth films of silver. The whisker growth can be understood on the basis of the ultramicroelectrode behaviour of the silver nuclei, the kinetics of the anodic and cathodic currents, and the surface properties of the silver crystals.