Pt-Ru catalysts of various compositions, between 0 and 100 at.% of Ru, were deposited onto N-doped multi-walled carbon nanotubes (N-CNTs) by atomic layer deposition (ALD) at 250 degrees C. The Pt and Ru precursors were trimethyl(methylcyclopentadienyl)platinum (MeCpPtMe3) and bis(ethylcyclopentadienyl)ruthenium (Ru(EtCp)(2)), respectively. O-2 was used as the reactant in both processes. The composition of the catalysts was easily tuned by varying the Pt-to-Ru ALD cycle ratio. The catalysts were tested toward the CO oxidation and methanol oxidation reaction (MOR) in a three-electrode electrochemical set-up. For the compositions investigated, the catalysts with a Ru content of 29 at.% exhibited highest catalytic activity. (C) 2014 Elsevier Inc. All rights reserved.