We report on Pt selectively photodeposited on oxides sites of Ti-, and W-carbon composites. The change of the lattice parameter strongly suggests that the metal center alloys with the metal centers of the oxides with a concomitant change of electronic properties favorable for oxygen reduction reaction in acid medium.

The oxygen reduction reaction (ORR) was investigated on carbon (XC-72) supported platinum nanoparticles, generated via the carbonyl chemical route and on oxide composites supported platinum generated via the UV-photo-deposition technique in sulfuric acid medium. The behavior of Pt/C was examined using a careful dosing of the catalyst loading spanning the range from 4.3 to 131 μg cm−2. The ORR electrochemical response of Pt/C (in line with recent literature data) is put into contrast with the Pt/oxide-composite systems. Our results point out that it is possible to use smaller amounts of catalyst for the ORR when platinum atoms interact with the oxide (anatase) surface of the substrate composite. Evidence of the incipient metal–substrate interaction is discussed in the light of the results of XRD experiments.