Non-enzymatic sensor based on a glassy carbon electrode modified with Ag nanoparticles/polyaniline/halloysite nanotube nanocomposites for hydrogen peroxide sensing

Abstract

Ag nanoparticles/polyaniline/halloysite nanotube (AgNPs/PANI/HNTs) nanocomposites were synthesized and used for fabricating nonenzymatic H₂O₂ sensor. AgNPs/PANI/HNTs nanocomposites were synthesized through the direct loading of preformed AgNPs over the surface of PANI/HNTs. The morphology and composition of the nanocomposites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectrum (EDX) and X-ray diffraction spectrum (XRD). SEM and TEM observations reveal that large numbers of AgNPs were distributed on the surface of PANI/HNTs. The electrochemical investigations indicate that the sensor based on AgNPs/PANI/HNT exhibited an excellent performance toward H₂O₂ with a wide linear range of 0.5 μM to 4.7 mM, a high sensitivity of 74.8 μA mM⁻¹ cm⁻² and a low detection limit of 0.3 μM (S/N = 3).