کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
220127 463316 2009 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Role of adsorbed species in methanol oxidation on Pt studied by ATR-FTIRAS combined with linear potential sweep voltammetry
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Role of adsorbed species in methanol oxidation on Pt studied by ATR-FTIRAS combined with linear potential sweep voltammetry
چکیده انگلیسی

Methanol adsorption/oxidation on a polycrystalline platinum electrode was investigated by ATR-FTIRAS combined with linear potential sweep voltammetry after initial adsorption at 0.05 V in 0.05–1.0 M HClO4 containing 0.04–1.0 M methanol. Methanol adsorption exhibits a pronounced maximum around 0.56 V, which coincides with the onset potential of the oxidation. This suggests that adsorbed CO is not a catalytic poison but an intermediate of the oxidation. The low methanol oxidation activity on Pt is not ascribed to the poisoning action by the adsorbed CO but to inability of Pt to dissociate water to adsorbed OH species needed for the CO and methanol oxidation. It was found for the first time that methanol adsorption at 0.05 V is significantly diminished in dilute perchloric acids. This was interpreted in terms of reduced physisorption of methanol at the adsorption potential which becomes more negative with respect to the pzc. Band intensity of the formate species with a symmetric O–C–O vibration around 1320 cm−1 remains unchanged with increase of methanol concentration from 0.04 M to 1 M, while the peak current of methanol oxidation increases by ca. three times in 1 M HClO4. The result suggests a minor role of the formate in the methanol oxidation mechanism.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Electroanalytical Chemistry - Volume 632, Issues 1–2, 1 July 2009, Pages 109–119
نویسندگان
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