| Abstract: | This work examines the charge transport properties of redox films of the immobilized enzyme mediator Os(bpy)2(picolinate)]Cl (Os(bpy)2Pic]+). Chronoamperometry was used to calculate DCT values (typically of the order of 1.5×10?8 cm2 s?1) and the effect of %loading of redox material was determined for three electrolytes over a range of concentrations. The data obtained implies that charge transfer within the film occurs via a redox site diffusion mechanism. The concentration of redox sites was determined using an approximate film thickness of 7 μm, as determined from profilometry studies. Experiments were also performed using immobilized carbon nanotubes within the redox film in order to examine the impact of the increased surface area and conductivity. The presence of the carbon nanotubes had the effect of doubling the surface coverage values and enhancing DCT1/2 CM values from 1.9×10?9 to 16.1×10?9 mol cm?1 s?1. |
