Fig. 3. UV-Vis redox difference spectra of bipyridine Co redox mediator complexes. UV-Vis reduced minus oxidized difference spectra for all six complexes were obtained using quartz split cuvettes for physical spectral subtraction. Ferricyanide was used as a chemical oxidant, and ascorbate as reductant. Samples were prepared in a 1 : 3 acetonitrile : H2O and incubated in the dark for 1 h at 22 °C before taking spectra.
