Diamond Nanoelectrode Arrays for the Detection of Surface Sensitive Adsorption. Issue 34 (11th July 2013)

• Record Type: Journal Article
• Authors: Hees, Jakob; Hoffmann, René; Yang, Nianjun; Nebel, Christoph E.
• Is Part Of: Chemistry. Volume 19:Issue 34(2013)
• Page Start: 11287
• Page End: 11292
• Publication Date: 2013-07-11
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201301763
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Nanocrystalline diamond nanoelectrode arrays (NEAs) have been applied to investigate surface‐sensitive adsorption phenomena at the diamond–liquid interface. The adsorption of neutral methyl viologen (MV⁰) was used as a model system. The adsorption of MV⁰ was examined on hydrogen‐ and oxygen‐terminated surfaces. On the hydrogenated nanoelectrode surface, a sharp anodic stripping peak was observed upon oxidation of MV⁰, revealing strong adsorption of MV⁰. In contrast, a sigmoidal voltammogram was recorded with an oxygenated electrode surface, indicating there was no MV⁰ adsorption. The changes in the shapes of these voltammograms are due to the drastic changes that occur in the diffusion profiles during the transition. The diffusion profile changes from hemispherical diffusion on oxygen‐terminated surfaces to thin‐layer electrochemistry upon adsorption on hydrogen‐terminated surfaces. Different types and concentrations of buffer solutions were then used to vary the interaction of MV⁰ with diamond NEAs. The results suggest that the adsorption of MV⁰ on hydrogen‐terminated diamond NEAs is controlled by hydrophobic interactions. Therefore, diamond NEAs are ideal for the study of adsorption phenomena at the liquid–solid interface with voltammetry.</p> </abstract>