Improvement of the electrochemical properties of as-grown boron-doped polycrystalline diamond electrodes deposited on tungsten wires using ethanol

The electrochemical properties of boron-doped diamond (BDD) polycrystalline films grown on tungsten wire substrates using ethanol as a precursor are described. The results obtained show that the use of ethanol improves the electrochemistry properties of as-grown BDD, as it minimizes the graphitic phase upon the surface of BDD, during the growth process. The BDD electrodes were characterized by Raman spectroscopy, scanning electronic microscopy, cyclic voltammetry ( CV), and electrochemical impedance spectroscopy ( EIS). The boron-doping levels of the films were estimated to be similar to 10(20) B/cm(3). The electrochemical behavior was evaluated using the Fe(CN)(6)(3-/4-) and Ru(NH3)(6)(3-/4-) redox couples and dopamine. Apparent heterogeneous electro-transfer rate constants k(app)(0) were determined for these redox systems using the CV and EIS techniques. k(app)(0) values in the range of 0.01-0.1 cm s(-1) were observed for the Fe(CN)(6)(3-/4-) and Ru(NH3)(6)(3-/4-) redox couples, while in the special case of dopamine, a lower k(app)(0) value of 10(-5) cm s(-1) was found. The obtained results showed that the use of CH3CH2OH (ethanol) as a carbon source constitutes a promising alternative for manufacturing BDD electrodes for electroanalytical applications.