A. Fitch et Rj. Krzysik, MULTISWEEP CYCLIC VOLTAMMETRIC STUDIES ON THE EFFECT OF CHARGE ON DIFFUSION AND SORPTION PROCESSES OF ML(3)(N-MODIFIED ELECTRODES() CHELATES AT CLAY), Journal of electroanalytical chemistry [1992], 379(1-2), 1994, pp. 129-134
The unique pattern of uptake of Cr(bpy)(3)(3+) at clay-modified electr
odes can be attributed to two factors as deduced from experiments with
Co(bpy)(3)(3+), Co(bpy)(3)(2+), and(-)d-Cr(bpy)(3)(3+). In the first
case, transport of the trivalent species is accelerated across the fil
m because of electrostatic considerations. The initial swelling of the
clay film controls the extent of accelerated transport through the fi
lm by establishing the interlayer dimensions. Valence, however, does n
ot completely control the pattern of loading of the clay film with the
complex. Cr(bpy)(3)(3+) and Co(bpy)(3)(3+) exhibit different rates of
adsorption by the clay surface which contribute to the differing non-
equilibrium loading patterns.