Electrochemical activity of boron-doped diamond electrodes grown on carbon fiber cloths

Electrochemical activity of doped CVD-diamond electrodes was investigated as a function of boron content connected with the films surface characteristics and morphology. A textured cloth of carbon fibers was used as a substrate with a discontinuous surface. It was treated using 0.25-mum diamond powder by ultrasound dispersion in hexane. The nucleation and coalescence of the diamond film around the fibers was evident. Boron-doped diamond electrodes have been analyzed in the range of acceptor concentrations of 10(18) and 10(21) cm(-3). Their electrochemical behavior was studied by cyclic voltammetry measurements in neutral (KCl, Na2SO4 and NaNO3) and acidic (HCl, H2SO4 and HNO3) solutions. The anodic and cathodic currents increase with the doping level and present a maximum when the electrodes reach a metallic behavior. For comparison, films grown on silicon substrate in similar conditions were also studied as standard diamond electrodes. Surface morphology and film quality was analyzed by scanning electron microscopy (SEM) and Raman scattering spectroscopy. (C) 2002 Elsevier Science B.V. All rights reserved.