Enhanced photocatalytic activity of La and Zr-codoped AgNbO₃ for rhodamine B and methylene blue degradation

In this study, AgNbO₃, 1%, 5%, and 10% La, Zr-codoped AgNbO₃ photocatalyst were synthesized by the solid state method. The synthesized AgNbO₃ was codoped with La and Zr to enhance its effectiveness in photocatalytic dye degradation. The as-synthesized materials were also characterized via XRD and SEM analysis to determine their structural and morphological properties. The vibrational bands of the photocatalysts observed in FT-IR spectroscopy confirmed the presence of NbO₆ octahedra which can be found in AgNbO₃. Furthermore, all the photocatalysts showed high crystallinity and are single-phase materials with an orthorhombic crystal structure. It was observed that the particle size decreased with the increasing concentration of La and Zr codopants. The calculated lattice parameters showed that codoping AgNbO₃ with 10% La and Zr had caused its unit cell volume to expand. The UV–Vis absorption spectra showed a slight band gap widening and a decrease in surface plasmonic resonance (SPR) effect with increasing La, Zr-codoping. The photocatalytic RhB and MB degradation results of undoped AgNbO₃ and La, Zr-codoped AgNbO₃ were compared and they showed that there are improvements in the photocatalytic performance. The highest degradation (98.1%) of RhB was achieved by 5% La, Zr-codoped AgNbO₃ while the highest MB degradation (48.3%) was achieved by 1% La, Zr-codoped AgNbO₃. Last but not least, La, Zr-codoped AgNbO₃ is a promising material for water remediation application as it showed enhanced performance for photocatalytic dye degradation under visible light irradiation.