An electrochemical sensor for Cd2+ based on the inducing adsorption ability of I-

Herein, an electrochemical sensor for sensitive and simple determination of Cd2+, was fabricated based on the excellent properties of acetylene black (AB) and strong inducing adsorption ability of I-. In pH 3.6 HAc-NaAc buffer containing 5.0 x 10(-3) mol L-1 I-, Cd2+ was induced to accumulate at AB paste electrode surface under the inducing adsorption of I-, and then reduced to Cd at -1.10V During the following potential sweep from -1.10 to -0.40V, reduced Cd was oxidized, resulting in a sensitive and well-shaped stripping peak at -0.83 V. Based on this, a new electrochemical method was developed for Cd2+, analysis. The linear range is found to be 5.0 x 10(-8) to 2.0 x 10(-6) mol L-1, and the detection limit is 2.0 x 10-8 mol L-1. Finally, this sensor was successfully used to detect Cd 21 in water samples. (c) 2006 Elsevier B.V. All rights reserved.