Hydrogen-assisted and CO-assisted reductive desorption of hydroquinone-derived adlayers from Pt(1 1 1) single crystal electrodes

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• 作者：Margarita Rodrí ; guez-Ló ; pez^a ; ^c ; Enrique Herrero^b ; Juan M. Feliu^b ; Paulino Tu&ntilde ; ó ; n^c ; Antonio Aldaz^b ; ^aldaz@ua.es ; Arnaldo Carrasquillo Jr.^d ; ^{carrasa@uprm.edu}
• 关键词：Hydroquinone ; Quinone ; Platinum ; Carbon monoxide ; Single crystal electrodes ; Reductive desorption
• 刊名：Journal of Electroanalytical Chemistry
• 出版年：2006
• 出版时间：1 September 2006
• 年：2006
• 卷：594
• 期：2
• 页码：143-151
• 全文大小：333 K

文摘

The hydrogen-assisted, reductive desorption of hydroquinone-derived adlayers (Q_(ads)) is reported at nearly defect-free Pt(1 1 1) single crystal electrodes in 0.5 M H₂SO₄. Classical electroanalytical techniques are used to evaluate surface packing density of Q_(ads) under a variety of conditions. Charge density measurements suggest that two limiting conditions are observed. High surface packing densities of the adsorbate are detected in the presence of 2 mM H₂Q_(aq), while lower surface packing densities are observed upon rinsing with 0 mM H₂Q_(aq) supporting electrolyte. A strong dependence between the mode of adsorption/desorption of Q_(ads) and the presence of long-range order at the Pt(1 1 1) electrode surface is revealed. The reductive displacement of Q_(ads) with CO is also reported. The experiments show that the extent of CO displacement can be controlled potentiometrically and that the progress of the displacement can be observed quantitatively through amperometric detection. Some additional applications of these novel electrochemical observations are discussed.