Ultrasound-Assisted Synthesis of Hybrid Phosphomolybdate–Polybenzidine Containing Silver Nanoparticles for Electrocatalytic Detection of Chlorate, Bromate and Iodate Ions in Aqueous Solutions

Herein, we report a hybrid electroactive material composed of silver nanoparticle-embedded polybenzidine matrix containing phosphomolybdic acid as the active inorganic component by an ultrasound-assisted method for the electrochemical detection of chlorate, bromate and iodate ions in aqueous solutions. The prepared hybrid material was characterised for its physicochemical properties: X-ray diffraction and transmission electron microscopy analyses provided evidence for the presence of silver nanoparticles (∼12 nm) in the hybrid material. The synthesized hybrid material was successfully fabricated on a glassy carbon electrode, and cyclic voltammetry was used to probe its electrochemical properties in 1 M H2SO4 solution. Amperometry was employed in order to find out the detection limits of chlorate, bromate and iodate ions in aqueous solutions. This hybrid electrochemical interface showed the lowest detection limits of 86.3 nM, 1.45 μM and 1.66 μM for bromate, iodate and chlorate, respectively. Phosphomolybdate anion (PMo12) present in the hybrid material acted as both effective mediator and the source of mobile protons at the electrochemical interface. Silver nanoparticles present in the hybrid material further influenced the electroactivity of the modified electrode.