In-situ polymerization of dendritic polyaniline nanofibers network embedded with Ag@SiO2 core-shell nanoparticles for electrochemical determination of trace arsenic(III)

Abstract

Arsenic(III) is a highly toxic pollutant in the environment, and the development of nanomaterials with high electrochemical activity for As(III) detection is a research focus at present. Herein, an electrochemical sensing platform based on polyaniline nanofibers embedded with Ag@SiO2 nanoparticles (Ag@SiO2/PANI NFs) was successfully constructed for trace As(III) determination. Owing to an in-situ chemical oxidation polymerization strategy, the polyaniline nanofibers loaded with Ag@SiO2 core-shell nanoparticles blossomed into the dendritic three-dimensional network. The unique structure with a huge specific surface area greatly enhanced the adsorption efficiency of As(III). Combined with the outstanding conductivity of polyaniline and the electrocatalytic ability of uniformly dispersed AgNPs, the stripping current signal of As(III) was further amplified. Based on the optimized conditions, the sensitivity of 0.83 μA μg−1 L was obtained in the linear range of 0.1 ~ 100 μg L−1 with a low detection limit of 0.013 μg L−1. And the selectivity, reproducibility, and long-term stability of this sensor were excellent. Additionally, satisfactory results were achieved by the recovery experiment of real samples, and the accuracy of this method was verified by comparison with ICP-MS. The above results demonstrated the promising application of the as-fabricated sensor in As(III) detection.