title: Structures and catalytic properties of PtRu electrocatalysts prepared via the reduced RuO2 nanorods array.
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 degrees C in vacuum or H2-reduction at 130 degrees 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>or=0.48 V.
authors.affiliation: Department of Chemical Engineering and Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei, 106 Taiwan.
authors.forename: Shih-Hui
authors.initials: SH
authors.lastname: Huang
authors.forename: Diah
authors.initials: D
authors.lastname: Susanti
authors.forename: Dah-Shyang
authors.initials: DS
authors.lastname: Tsai
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Hsieh
authors.forename: Ying-Sheng
authors.initials: YS
authors.lastname: Huang
authors.forename: Wen-Hung
authors.initials: WH
authors.lastname: Chung