Hierarchically grown ZnFe2O4-decorated polyaniline-coupled-graphene nanosheets as a novel electrocatalyst for selective detecting p-nitrophenol

In this study, a novel hierarchical-assembly approach was developed to for the co-assembly of ZnFe2O4 nano particles (NPs) and graphene-coupled polyaniline (PANI) nanosheets with the facilitation of graphene oxide (GO). Three-dimensional ultralight and porous ZnFe2O4/PANI@ reduced graphene oxide (rGO) aerogels were developed as effective and convenient electrochemical sensors for the detection of p-nitrophenol (p-NP). These ternary aerogels displayed efficient reduction ability and outstanding p-NP electrochemical sensing performance, which is attributed to the synergies between the local conductivity of the PANI@rGO nanosheets and the longdistance conductivity of the three-dimensional graphene aerogel frameworks. The experimental results demonstrated that the satisfactory linear concentration range for the detection of p-NP by ternary aerogels was 1-100 mu mol/L with excellent sensitivity at 36.898 mA mM(-1) cm(-2), along with excellent stability and selectivity (<2.4%). Importantly, the detection reliability of tap water was estimated, and an average recovery of 101.16% was maintained. Overall, the developed sensor displayed excellent electrochemical performance, and hierarchical assembly could provide a distinctive method for the fabrication of three-dimensional sandwich-like structured ternary nanocomposites with versatile applications.

Automated summary

A novel hierarchical-assembly approach was developed for the co-assembly of ZnFe2O4 NPs and graphene-coupled PANI nanosheets, resulting in the fabrication of ultralight and porous ZnFe2O4/PANI@rGO aerogels for efficient electrochemical detection of p-NP. These ternary aerogels exhibited excellent reduction ability and outstanding p-NP sensing performance, with a wide linear concentration range and high stability, making them suitable for accurate detection in tap water.