کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7739812 1497992 2013 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Efficient Pt/carbon electrocatalysts for proton exchange membrane fuel cells: Avoid chloride-based Pt salts!
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Efficient Pt/carbon electrocatalysts for proton exchange membrane fuel cells: Avoid chloride-based Pt salts!
چکیده انگلیسی
The catalytic layers of Proton Exchange Membrane (PEM) fuel cells use carbon-supported Pt-based nanoparticles, which are classically synthesized by impregnation with a metal precursor usually based on chloride counter-ions. However, the literature points out that chloride ions poison the catalytic activity. The purpose of this work is to compare the surface reactivity and the electrocatalytic activity of Pt/carbon xerogel nanoparticles contaminated with different amount of chlorine. The catalysts were synthesized using the Strong Electrostatic Adsorption (SEA) method and H2PtCl6 as a metal precursor. The Cl content in the catalysts was changed by varying the gas atmosphere and the duration of the reduction step. The effect of Cl contamination was investigated on two model reactions: the electrochemical COads oxidation and the O2 reduction. Evidences are provided that the Cl− ions issued from the incomplete decomposition/removal of the metal precursor partially block the Pt catalytic sites, and limit the rate of the COads + OHads recombination and of the diffusion of COads molecules in CO stripping experiments. The adsorption of Cl− ions also depreciates the ORR kinetics. In search for efficient catalysts, chloride-containing metal precursors must therefore be avoided.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Power Sources - Volume 240, 15 October 2013, Pages 294-305
نویسندگان
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