Synthesis and characterization of a heterogeneous ternary nanocomposite photocatalyst BiFeO3-Graphene-NaNbO3 for the degradation of MB dye disrupting pulmonary organs

Abstract

A maiden attempt to synthesize ternary nanocomposites of Bismuth Ferrite-Graphene-Sodium Niobate (BiFeO₃-Graphene-NaNbO₃) has been made by utilizing conventional solution method. Systematic increase in the loading concentrations of graphene on BiFeO₃-NaNbO₃ heterogeneous composites found to have influenced their structural parameters, optical properties, photocatalytic dye degradation and their dielectric properties and they were assessed from powder X-ray diffraction (XRD), Raman spectral measurements, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), optical absorption spectra in UV–Visible-Near IR region, Photoluminescence (PL) studies, photocatalysis and dielectric analyses. As such, admixture of graphene concentration of 0.025 percent with BiFeO₃-NaNbO₃ composite powders capable of degrading the methylene blue (MB) dye upto a maximum efficiency of 92% within the time frame of 120 min. Strikingly, at the same graphene concentration of 0.025 percent, the synthesized ternary composite sample exhibits an increased dielectric constant value of ‘37′. A close parallelism between the dielectric behaviour and photocatalytic dye degradation properties could be predicted from this study. Further, among various loading concentrations of graphene with BiFeO₃-NaNbO_3, lower concentration of 0.025 percent of graphene has been found as the optimum one for the improved MB dye degradation characteristics of the ternary composites of BiFeO₃-Graphene-NaNbO₃ with enhanced suppression of carrier recombination. The other interesting results have been discussed in detail.