Direct determination of arsenate based on its electrocatalytic reduction at the poly(aniline-co-o-aminophenol) electrode

It was found that the copolymer poly(aniline-co-o-aminophenol) (PANOA) can strongly catalyze the reduction of arsenate in a NaCl Solution. which was proved by cyclic voltammetry and the determination of activation energy. On the basis of the electrocatalytic reduction of arsenate, the PANOA copolymer was used as a probe to determine directly arsenate. The electrocatalytic activity of the PANOA electrode toward As(V) reduction strongly depended on the pH and the applied potential. Under the optimal conditions, the PANOA electrode can be used to determine directly As(V) concentration in a wide linear range (n = 19) of 0.949 and 495 mu M with a correlation coefficient of 0.995 and a limit of detection of 0.495 mu M. The sensitivity of the electrode was 0.192 mu A mu M-1 cm(-2). The PANOA electrode had the good storage stability and a less negative operation potential of -0.15 V (vs. SCE). (c) 2009 Elsevier B.V. All rights reserved.