Electrocatalytic reduction of nitrite at polypyrrole nanowire–platinum nanocluster modified glassy carbon electrode

Abstract

Pt nanoclusters were deposited in polypyrrole (PPy) nanowires by cyclic voltammetry method, fabricating a PPy–Pt nanocomposite on glassy carbon electrode (PPy–Pt/GCE). The electrocatalytic reduction of nitrite at PPy–Pt/GCE has been investigated using 0.5 M H 2SO 4 solution. The sensor exhibited excellent electrocatalytic activity toward nitrite reduction. In acidic medium, the cyclic voltammetry at 20 mV s − 1 gave a nitrite reduction peak at − 0.124 V with 0.566 μA μM − 1 current sensitivity in the range of 5.0 × 10 − 7 –1.0 × 10 − 3 M. The detection limit was 1.5 × 10 − 7 M ( s/ n = 3). The proposed method was successfully applied in the detection of nitrite in real water samples and obtained satisfactory results. The PPy–Pt composite modified electrode had good storage stability, reproducibility and anti-interference ability.