کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6661734 1426556 2018 32 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Squaric acid adsorption and oxidation at gold and platinum electrodes
ترجمه فارسی عنوان
جذب و اکسیداسیون اسکوریک اسید در الکترودهای طلا و پلاتین
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی
The adsorption and oxidation of squaric acid (3,4-dihydroxycyclobut-3-ene-1,2-dione, H2C4O4, SQA) at platinum and gold electrodes were studied spectroelectrochemically in perchloric acid solutions. Voltammetric experiments demonstrate that reversible adsorption takes place at gold electrodes in the double-layer region. As a difference with platinum electrodes, no dissociative adsorption processes leading to the blocking of the electrode surface are detected. ATR-SEIRAS experiments show potential-dependent adsorbate bands at potentials below 1.20 V vs RHE that, according to DFT calculations, can be assigned to adsorbed squarate. For platinum electrodes, the potential-dependent adsorption of squarate anions is coupled with the oxidative stripping of adsorbed carbon monoxide, which is formed upon dissociative SQA adsorption. Bonding of squarate species to the platinum and gold surfaces involves two oxygen atoms in a bidentate configuration, with the molecular plane perpendicular to the metal surface. The ATR-SEIRA spectra obtained for gold electrodes in the SQA oxidation region show bands for adsorbed bicarbonate anions formed from dissolved carbon dioxide molecules. In the case of platinum, distinct bands are observed for adsorbed oxidation products which probably are formed upon opening of the SQA ring.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Electroanalytical Chemistry - Volume 819, 15 June 2018, Pages 178-186
نویسندگان
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