Novel Electrode Material for Synthesis of Low Concentration Sodium Hypochlorite Solutions

The overpotential of oxygen evolution reaction is 700-800 mV more positive at FTO anode than on Pt electrode. This property of FTO coating makes it attractive as an electrode material for electrochemical sensors and electroanalytical chemistry. However, oxygen transfer reactions, such as Pb and Cl oxidation, occur with considerably lower overpotential. It indicates the possibility of formation of oxygen-containing particles which are adsorbed on the FTO surface at 1.5–1.6 V vs Ag/AgCl. Similar kinetics of galvanostatic formation of hypochlorite-ions on the Pt and FTO surface can indicate the similar character, surface concentration, and the energy of adsorbed radical-type particles. FTO coating thereby shows high electrocatalytic activity towards the synthesis of sodium hypochlorite during the electrolysis of dilute NaCl solutions. The preparation of new electrodes with electrocatalytic properties toward oxidation reactions was performed by electrodeposition of lead dioxide onto glass substrates covered with FTO. The modification of FTO electrodes with PbO2 leads to more conductive electrodes with an improved donor density. The electrodes have been designed for oxygen generation.