Ionic and electronic conductivity of the surface film on titanium during pulse electrolysis of water

The processes of corrosion and degradation of electrode materials are crucial for the efficiency of pulse electrolysis and are expected to depend on the electrical characteristics of the pulse (current/voltage, frequency, duty cycle). The aim of the present paper is to investigate the effect of these characteristics on the electrochemical properties of Ti electrodes. Pulse electrolysis was carried out in 6 M KOH for 24 and 72 h with current amplitude of 65 mA, frequencies of the signal of 0.5-10 kHz and pulse duty cycle between 1 and 99%. The electrochemical properties of the titanium anode and cathode surfaces after operation were characterized by electrochemical impedance spectroscopy in a borate buffer solution (pH 7.4) at the open circuit potential, as well as by linear sweep voltammetry in a similar solution containing an equimolar mixture of K4Fe(CN)6 and K3Fe(CN)6 as a redox couple to probe the electronic conductivity of the surface films