Platinum nanoparticles photo-deposited on SnO2-C composites: An active and durable electrocatalyst for the oxygen reduction reaction.

Platinum nanoparticles (NPs) were photo-deposited on SnO 2 -C nanocomposites prepared by sol-gel method. Surface morphology of the prepared materials, examined by scanning electron microscopy (SEM) and transmission electron microscopy, confirmed selective deposition of Pt NPs on SnO 2 nanoclusters formed on carbon surface. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) analysis, cyclic voltammetry (CV) and CO stripping experiments revealed modification of the electronic properties of the Pt NPs photo-deposited on the oxide-carbon composite in comparison to Pt/C prepared by the carbonyl chemical route. Rietveld refinement was employed to identify existing phases of catalysts and to determine the crystallite size. Micro-strain and intrinsic stacking fault increased and decreased, respectively, as a function of crystallite size. Pt loadings were determined by inductively coupled plasma mass spectrometry (ICP-MS). The oxygen reduction reaction (ORR) activity of the electrocatalysts was investigated in acid media using the rotating disk electrode (RDE) system. Accelerated durability test (ADT) results showed that photo-deposited Pt nanoparticles onto SnO 2 -C nanocomposite are more durable than those chemically deposited on carbon. • Pt/SnO 2 -C composite electrocatalysts were prepared by photo-deposition. • For comparison, platinum nanoparticles were chemically deposited on carbon. • Metal-support interaction was studied by physical and electrochemical characterization. • Pt/SnO 2 -C catalysts showed high oxygen reduction activity in acid media. • Durability of the Pt/SnO 2 -C catalyst was superior in comparison with Pt/C. [ABSTRACT FROM AUTHOR]