Novel attapulgite/polyaniline/phosphomolybdic acid-based modified electrode for the electrochemical determination of iodate

• Attapulgite was used as a template to control size and morphology of polyaniline.
• Phosphomolybdic acid was stably anchored on attapulgite/PANI composite.
• Attapulgite/PANI/PMo12/GCE showed perfect electrocatalytic activity to iodate.
• Detection limit of attapulgite/PANI/PMo12/GCE for iodate was found to be 0.53 μM.

A novel attapulgite/polyaniline/phosphomolybdic acid-based amperometric sensing platform was constructed for the determination of iodate. Nanostructured attapulgite was utilized for reducing agglomeration of polyaniline particles, and the as prepared attapulgite/polyaniline composite was used to immobilize phosphomolybdic acid. Excellent electrocatalytic performance was obtained due to the synergistic effect of nanostructured attapulgite, polyaniline and phosphomolybdic acid. The electrochemical responses of as prepared modified electrode were investigated by cyclic voltammetry and chronoamperometry. The modified electrode exhibited linear amperometric response for iodate in the concentration range of 2.0 × 10−6 M–5.2 × 10−4 M (R = 0.999). The detection limit was calculated as 5.3 × 10−7 M. Good reproducibility, high stability, fast amperometric response, and possibility of rapid preparation were also great advantages of this modified electrode. Based on this work, the attapulgite/polyaniline/phosphomolybdic acid modified electrode was successfully applied to determine iodate in a commercial table salt sample.

Shown in left were CVs on attapulgite/PANI/PMo12/GCE at different scan rates in the range of 10–500 mV/s in 0.50 M H2SO4 + 0.50 M Na2SO4 solution. Shown in right was current–time plot of iodate with increasing concentrations on attapulgite/PANI/PMo12/GCE in 0.50 M H2SO4 + 0.50 M Na2SO4 solution.Figure optionsDownload as PowerPoint slide