Details

Autor(en) / Beteiligte

• Ugo, Paolo
• Moretto, Ligia M.
• Silvestrini, Morena
• Pereira, Francisco C.

Titel

Nanoelectrode ensembles for the direct voltammetric determination of trace iodide in water

Ist Teil von

• International journal of environmental analytical chemistry, 2010-08, Vol.90 (9), p.747-759

Ort / Verlag

Abingdon: Taylor & Francis Group

Erscheinungsjahr

2010

Quelle

Taylor & Francis Journals Auto-Holdings Collection

Beschreibungen/Notizen

• Procedures for the preparation and characterisation of ensembles of gold nanodisk electrodes (NEE) of 30 nm diameter are presented, in particular focusing on improvements in the signal/background current ratios and detection limits with respect to the electrochemical oxidation of iodide and its analytical determination in water samples. At NEEs iodide undergoes a quasi-reversible diffusion controlled oxidation with a slight shift in E 1/2 values and slightly higher peak to peak separation with respect to conventional gold disk electrodes. The double layer charging current at the NEE is significantly lower than at conventional electrodes so that the detection limit (DL) by cyclic voltammetry with NEEs in tap water is significantly lower than DL at the Au-disk millimetre-sized electrode (DL 0.3 µM at NEE vs. 4 µM for Au-disk). Finally, it is shown that NEEs in combination with square wave voltammetry can be applied for the direct determination of iodide in water samples from the lagoon of Venice, with a detection limit of 0.10 µM.