Web Release Date: February 1,
Structures and Catalytic Properties of PtRu Electrocatalysts Prepared via the Reduced RuO2 Nanorods Array
and
Department of Chemical Engineering and Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei, 106 Taiwan
Received August 22, 2007
In Final Form: November 17, 2007
Abstract:
Structures and properties of PtRu electrocatalyts, derived from the aligned RuO2 nanorods (RuO2NR), are investigated
using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron
spectroscopy, and cyclic voltammetry toward COads and methanol oxidation. The catalytic activity of methanol oxidation
and the CO tolerance are promoted significantly by reducing RuO2 into Ru metal before decorating with Pt. Reduction
of RuO2NR was carried out by either thermal decomposition at 650 
C in vacuum or H2-reduction at 130 C in
low-pressure hydrogen. Reduction assisted by hydrogen allows infiltrating decomposition at low temperature and
produces an array of nanorods with rugged walls featuring small Ru nuclei and larger surface area. Pt-RuNR, whose
surface Pt:Ru ratio = 0.58:0.42 was prepared by decorating with 0.1 mg cm-2 Pt on the H2-reduced array containing
0.39 mg cm-2 Ru, demonstrates a favorable combination of CO tolerance and high methanol oxidation activity superior
to other RuO2NR-derived catalysts. When compared with a commercial electrocatalyst of PtRu (1:1) alloy (<4 nm),
the activity of Pt-RuNR in methanol oxidation is shown to be somewhat lower at potential <0.48 V and higher at
potential 
0.48 V.
Download the full text: PDF | HTML
