Collect. Czech. Chem. Commun. 1991, 56, 309-316

Generation of hydrogen peroxide by reduction of oxygen in semihydrophobic trickle electrodes

Otomar Špalek and Karel Balogh

Institute of Inorganic Chemistry, Czechoslovak Academy of Sciences, 160 00 Prague 6


The reduction of oxygen to hydrogen peroxide was studied in semihydrophobic trickle electrodes prepared from crushed graphite and teflonized carbon black. The potential of these electrodes was found markedly more positive and the peroxide current yields appreciably higher than for electrodes made of used crushed graphite. The reason for this is the higher surface area of the electrodes containing carbon black and occurrence of a three-phase interface in them. The relevant properties, i.e. electric resistance, electrolyte holdup, polarization curves for the oxygen reduction and pexide current yields, were also studied for trickle electrodes containing graphite felt. The electrochemical activity of electrodes made from untreated felt was found rather low but it increased several times when felt pretreated by oxidation was used.