Design and Construction of Polyaniline/Reduced Graphene Oxide Three-Dimensional Dendritic Architecture on Interdigital Electrode for Sensitive Detection Nitrite

Abstract

The polyaniline/reduced graphene oxide (PANI/RGO) modified interdigital electrode (IDE) has been successfully fabricated by in situ electrochemical reduction and electrochemical polymerization through cyclic voltammetry. The morphology and topography of PANI/RGO characterized by SEM and AFM display intercross-linked dendritic structure in three dimensions, and it is favorable for the detection of nitrite due to its large surface area, which can provide the large electrocatalytic active surface and various diffusion paths for nitrite. Herein, the obtained PANI/RGO/IDE was employed for the electrochemical monitoring platform of nitrite for the first time and the electrochemical performance of the as-developed sensor was investigated via cyclic voltammetry and chronoamperometry. At the optimum conditions, the PANI/RGO/IDE has a linear response in the range from 0.4 to 183.7 mM with a sensitivity of 457.4 μA mM−1 cm−2 and a detection limit of 0.1 μM. Moreover, the obtained PANI/RGO/IDE with excellent long-term stability and reproducibility also can be employed for practical application for the determination of nitrite in tap water, the results show that the recovery rate is desirable. It is expected that IDE can be employed as the substrate electrode decorated with various materials to construct high-performance electrochemical sensors.