Kinetic study of oxygen reduction reaction and PEM fuel cell performance of Pt/TiO2-C electrocatalyst

The electrochemical activity and thermal stability of the Pt/TiO2-C were evaluated in the oxygen reduction reaction (ORR) in acid medium at different temperatures. The platinum was selectively deposited onto the TiO2 (Ebg = 2.3 eV) by the photo-irradiation of platinum precursor (Pt4+→Pt0). The Pt/TiO2-C electrocatalyst prepared was characterized by XRD, TEM/EDS, cyclic and lineal voltammetry techniques. TEM images indicated that platinum nanoparticles (<5 nm) were deposited in agglomerates form around the oxide sites. EDS and XRD results confirm the composition and crystalline structure of Pt/TiO2-C. The thermal stability and electrochemical activity of the Pt/TiO2-C for ORR at different temperatures (298–343 K) is higher than Pt/C commercial sample (Pt-Etek). A more favorable apparent enthalpy of activation for Pt/TiO2-C was greatly influenced by addition of oxide in the catalyst compare to Pt-Etek. Single H2/O2 fuel cell performance results of Pt/TiO2-C show an improvement of the power density with the increase of the temperature.