Electron transfer kinetics of ferrocene at microcrystalline boron-doped diamond electrodes: Effect of solvent and electrolyte

Cyclic voltammetric measurements were made using well-characterized microcrystalline boron-doped diamond thin-film electrodes to test the material's responsiveness for ferrocene as a function of scan rate, solvent, and electrolyte composition. Apparent heterogeneous electron transfer rate constants, k^o_app, of 0.042 ± 0.015, 0.048 ± 0.015, and 0.008 ± 0.002 cm/s were observed in 0.1 M NaClO₄/CH₃CN, 0.1 M TBAClO₄/CH₃CN, and 0.1M TBAClO₄/CH₂Cl₂, respectively. These rate constants, obtained using electrodes without any type of pretreatment, are similar to those observed for freshly polished glassy carbon. The results demonstrate that boron-doped diamond is a viable material for the electrochemical analysis of nonaqueous analytes.