Temperature dependence of oxygen reduction mechanism on a titanium oxide–based catalyst made from oxy–titanium tetra–pyrazino–porphyrazine using carbon nano-tubes as support in acidic solution

Kinetic analysis of the oxygen reduction reaction (ORR) was performed on a titanium oxide–based cathode in 0.1M HClO4 based on the Damjanovic model by using a rotating ring disk electrode, as proposed by Hsueh et al. The titanium oxide–based cathode, produced from oxy–titanium tetra–pyrazino–porphyrazine via oxidation under a low partial pressure of oxygen using carbon nano-tubes as support, showed high reactivity in the four–electron reduction of O2. In addition, we applied Hsueh’s method to the study of the temperature dependence of the ORR for the first time. The activation energies of the four–electron reduction reaction at an overpotential of −0.40V and the two–electron reduction reaction at an overpotential of −0.50V were calculated to be 45.6 and 45.5kJmol−1, respectively.