Bismuth-coated glassy-carbon electrodes have been successfully applied for catalytic adsorptive-stripping voltammetric measurements of low levels of vanadium(V) in the presence of chloranilic acid (CAA) and bromate ion. The new protocol is based on the accumulation of the vanadium-chloranilic acid complex from an acetate-buffer (pH 5.5) solution at a preplated bismuth film electrode held at -0.35 V (vs. Ag/AgCl), followed by a square-wave voltammetric scan. Factors influencing the adsorptive stripping performance, including the CAA and bromate concentrations, solution pH, and accumulation potential or time have been optimized. The response compares favorably with that observed at mercury film electrodes. A linear response is observed over the 5 - 25 ug/L concentration range (two min accumulation), along with a detection limit of 0.20 ug/L vanadium (10 min accumulation). High stability is indicated from the reproducible response of a 50 ug/L vanadium solution (n=25; RSD = 3.1%). Applicability to a groundwater sample is illustrated.
Revised: June 29, 2009 |
Published: June 1, 2006
Citation
Wang J., D. Lu, S. Thongngamdee, Y. Lin, and O.A. Sadik. 2006.Catalytic Adsorptive Stripping Voltammetric Measurements of Trace Vanadium at Bismuth Film Electrodes.Talanta 69, no. 4:914-917.PNNL-SA-47950.