Electrochemical determination of low levels of uranyl by a vibrating gold microelectrode

Y. Peled, E. Krent, N. Tal, H. Tobias, D. Mandler*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

43 Scopus citations

Abstract

In this work we report the sensitive electroanalytical detection of uranium(VI) in aqueous solutions. Uranium commonly exists in aqueous solutions in the form of its oxo ion, uranyl (UVIO22+). The detection of uranyl has been accomplished by us through its deposition upon reduction by two electrons to the insoluble UO2 using a bare disk gold macroelectrode and anodic stripping voltammetry (ASV). This gave an unsatisfactory detection limit of ca. 1 × 10-5 M uranyl. Moreover, the evolution of hydrogen bubbles blocked the electrode surface as a result of water reduction at negative deposition potential (-0.7 V vs Ag/AgCl). The application of a 25 μm diameter Au microwire electrode on which UO2 precipitated at negative potential (-1.2 V) improved substantially the detection limit. Further improvement was accomplished by vibrating the microwire working electrode, which increased the amounts of UO2 deposition due to decreasing the diffusion layer. The effect of the vibrating amplitude and frequency on the electroanalytical response was studied and optimized. Eventually, a detection limit of ca. 1 × 10-9 M uranyl was achieved using a 5 min deposition time, -1.2 V deposition potential, and vibrating the electrode at frequency of 250 Hz and amplitude of 6 V.

Original languageAmerican English
Pages (from-to)768-776
Number of pages9
JournalAnalytical Chemistry
Volume87
Issue number1
DOIs
StatePublished - 6 Jan 2015

Bibliographical note

Publisher Copyright:
© 2014 American Chemical Society.

Fingerprint

Dive into the research topics of 'Electrochemical determination of low levels of uranyl by a vibrating gold microelectrode'. Together they form a unique fingerprint.

Cite this