| Boron doped diamond is a promising functional material due to itsexcellent physical and chemical properties including improving electricconductivity and good electrochemistry. In this paper, B-doped diamond weresynthesized under high pressure and high temperature using B-doped graphiteintercalation compositions (GICs) as carbon sources. The electrochemistrycharacteristic of B-doped diamond powder microelectrode was discussed bymeasuring the cyclic voltammetry curves and impedance spectra.The cyclic voltammetry measurements in aqueous electrolyte solutions ofKCl, Na2SO4 and H2SO4 showed that B-doped diamond powder microelectrodehas wide potential windows and low background current. And the cyclicvoltammetry was used in the solutions containing K3Fe(CN)6/K4Fe(CN)6, it wasdemonstrated that the electrochemical process of the B-doped diamond powdermicroelectrode was a quasi-reversible one. The peak separation (?Ep) enlargedwith the increasing of scan rate or the concentration of K3Fe(CN)6/K4Fe(CN)6.The linear relation between peak current (Ip) and square root of scan rate (v1/2)showed that the electrode process was a diffusion-controlled mass transportprocess.Electrochemical impedance spectroscopy was applied in the electrolytesolutions of KCl and KCl containing K3Fe(CN)6/K4Fe(CN)6. The results showedthat electrode reaction was controlled by charge transfer process and diffusionprocess. Powder microelectrode was expressed with porous characteristics. Andthe obtained spectra were analyzed with an equivalent circuit model.
|
PDF Full Text Request