Biogenic synthesis of LiNiVO4 nanoparticles for the evaluation of photocatalytic and electrochemical applications

In this present work, lithium nickel vanadate nanoparticles (LiNiVO4 NPs) were synthesized by solution combustion method. Here, jackfruit seed extract is employed as a fuel for the synthesis. These nanoparticles were characterized by various spectroscopic techniques. X-ray diffraction (XRD) studies confirm the inverse spinel structure of LiNiVO4 NPs. The scanning electron microscopy (SEM) images represent the agglomerated and clustered-like structure of NPs. Energy dispersive X-ray (EDX) spectrometry shows the existence of vanadium, nickel, and oxygen elements. Also, Ni and V are present in the average ratio of 1:1. The UV-visible spectral analysis indicated absorption bands at 465 and 728 nm, corresponding to a band gap energy of 2.2 eV. The vibrational analysis of the NPs was confirmed through IR and Raman spectroscopy, with a new peak observed at 1036 cm(-1) indicating the bond interaction of Li+-O-V in the FTIR analysis. Further, LiNiVO4 NPs exhibit good photocatalytic activity for the degradation of methylene blue (MB) dye under visible light irradiation. And the percentage of degradation efficiency is 91.77 around 180 min. The photocatalytic activity was due to the production of OH radicals during photo irradiation on LiNiVO4 NPs. The effect of different parameters on photo-catalytic activity was also studied in detail, including dye concentration, catalytic quantity, pH variation, scavenger activity, and recycling of the catalyst. Electrochemical impedance spectroscopy analysis revealed lower charge transfer and good ionic conductivity of LNV NPs, and it is also suitable for supercapacitor preparation.