Naslov
Spreading and detachment of organic droplets at an electrified interface

Autori
Ivošević, Nadica ; Žutić, Vera

Izvornik
Langmuir (0743-7463) 14 (1998); 231-234

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
detachment; mercury electrode; organic droplets; spreading

Sažetak
We communicate the preliminary results of simple spreading and detachment experiments at a stationary mercury electrode. The effect of potential is observed on the organic droplets deposited at the mercury pool/aqueous electrolyte interface. Shape and detachment of droplets of insoluble organic liquids hexadecane, squalene and methyl oleate are controlled by the applied potential and buoyancy. At the potential of zero charge of the metal and maximum adhesion force, droplets form lenses with the largest contact area, but they do not spread completely to a film. By scanning potential beyond the critical value of wetting the contact area reduces and the droplets shape changes towards ideal sphere. The particular shapes are perfectly reproducible and stable at constant potentials. Detachment of the droplets by buoyancy takes place only when the applied potential largely exceeded the critical potential of wetting. The difference between experimentally observed potential of detachment of hexadecane droplets and the critical potential of wetting ( E>700mV) is ascribed to modification of the mercury surface by a hexadecane monolayer. Separately performed modification of the mercury interface by a monolayer of adsorbed dextran had a similar effect on the shape and detachment of hexadecane droplets, while droplets of more polar organic liquids (squalene and methyl oleate) showed a complex dynamics and instability phenomena.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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