کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
194715 459798 2008 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thermodynamic analysis of (bi)sulphate adsorption on a Pt(1 1 1) electrode as a function of pH
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Thermodynamic analysis of (bi)sulphate adsorption on a Pt(1 1 1) electrode as a function of pH
چکیده انگلیسی

A complete thermodynamic study of (bi)sulphate adsorption on Pt(1 1 1) electrodes from solutions at four different pHs (pH 0.43, 2.1, 3.1 and 4.1) is reported. The effect of pH on the sum of the Gibbs excesses of sulphate and bisulphate species, standard Gibbs energies of adsorption and formal partial charge numbers is analyzed. The results provide relevant information on the nature of species involved in the different voltammetric features. The experiments at pH 0.43 were performed in a higher base electrolyte concentration (0.5 M), that allows the study of (bi)sulphate adsorption in a broader range of concentrations. Under these conditions, two adsorption steps are clearly defined, associated to two different voltammetric features, between 0.30 and 0.60 V and between 0.65 and 0.90 V (standard hydrogen scale, SHE). Once the pH is increased, a marked decrease in absolute value of the (bi)sulphate adsorption Gibbs energy is observed, concomitant with an increasing amount of OH co-adsorption.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 53, Issue 23, 1 October 2008, Pages 6793–6806
نویسندگان
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