Direct observation of a nonequilibrium electro-osmotic instability.
We present a visualization of the predicted instability in ionic conduction from a binary electrolyte into a charge selective solid. This instability develops when a voltage greater than critical is applied to a thin layer of copper sulfate flanked by a copper anode and a cation selective membrane. The current-voltage dependence exhibits a saturation at the limiting current. With a further increase of voltage, the current increases, marking the transition to the overlimiting conductance. This transition is mediated by the appearing vortical flow that increases with the applied voltage.
Rubinstein
S M
SM
Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel. robinst@bgu.ac.il
Manukyan
G
G
Staicu
A
A
Rubinstein
I
I
Zaltzman
B
B
Lammertink
R G H
RG
Mugele
F
F
Wessling
M
M