Ecofriendly synthesis of NiZnFe2O5 nanoparticle by papaya leaf extract for electrochemical detection of ascorbic acid in orange juice and pharmaceuticals

A green technique has been employed to synthesize the NiZnFe2O5 nanoparticles using papaya leaf extract. The X-ray diffraction investigated the structural characteristics and crystalline size. The morphology of the synthesised nanoparticle is analysed by scanning electron microscopy. The average diameter of the nanoparticle is 47.93 nm, which was determined using the dynamic light scattering method. UV/Vis diffuse reflectance spectrum results revealed that the NiZnFe2O5 NPs band gap is 1.8 eV. It was calculated using the Kubelka-Monk function and energy dispersion X-ray spectroscopy analysis was used to identify the synthesized nanoparticle's elements. The electrochemical behaviour of NiZnFe2O5 modified glassy carbon electrode (GCE) nd bare GCE was studied to detect ascorbic acid using cyclic voltammetry and differential pulse voltammetry. Compared to unmodified GCE, NiZnFe2O5 nanoparticles modified GCE exhibit excellent electrocatalytic activity towards the AA oxidation, which was proved by the increase in peak current and decrease in peak potential. Electrochemical impedance analysis suggests that the NiZnFe2O5 nanoparticles significantly enhance the charge transfer rate. The linear response of the peak current on the concentration of AA was obtained in the range of 0.2-50 µM. The detection limit was found to be 1.038 µM. The present work serves as a systematic benchmark to assess the electrochemical sensing potential of NiZnFe2O5 NPs towards AA in orange juice and pharmaceuticals.