Improved ORR activity and long-term durability of Pt nanoparticles deposited on TiO₂-decorated multiwall carbon nanotubes

Titanium dioxide coatings of different thicknesses were deposited on the acid-treated multiwall carbon nanotubes (MWCNTs) using controlled atomic layer deposition (ALD). Pt nanoparticles (NP) were deposited on TiO₂/MWCNT supports using two deposition methods, viz. sputter-deposition and photo-deposition. Scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) measurements revealed successful application of ALD for the deposition of TiO₂. Both magnetron sputtering and photo-deposition were found to be efficient and well-controlled techniques for the deposition of Pt NPs on oxide-carbon support. Electrochemical decontamination and characterization of the catalysts surfacewas carried out by CO stripping and cyclic voltammetry in 0.1 M KOH solution. The prepared Pt-TiO₂/MWCNT catalyst showed comparable oxygen reduction reaction (ORR) activity to that of commercial Pt/C (20 wt%), while long-term durability test revealed better durability of the prepared catalysts due to strong metal-support interaction.