Barium and strontium doped La-based perovskite synthesis via sol-gel route and photocatalytic activity evaluation for methylene blue

Abstract

In the current work, a La-based nanocomposite (LaxBa1−xSryCd1−yO3±δ) has been synthesized via sol-gel method. The influence of Ba and Sr doping on the structural, dielectric and photocatalytic characteristics of La-based perovskite nanocomposite has been investigated. The synthesized material was characterized employing different techniques such as FTIR, XRD, which confirmed the formation of nanocomposite. Representative peaks of metal oxygen bonds (M–O), in FTIR spectra confirmed the formation of the product. Orthorhombic crystalline structures having particle size 89.92 nm was confirmed by XRD analysis. Dielectric studies were conducted for the synthesized nanocomposite. The real and imaginary dielectric constant exhibited conservation and consumption of energy and AC conductivity analysis elaborated the effect of frequency on conductivity of the synthesized sample. Doping of nanomaterial with Ba and Sr caused inhomogeneity in the structure that caused reduction in number of moving charges due to which dielectric constant was found maximum at lower frequency. Enhanced dielectric properties caused a decrement in energy losses with increasing frequency. The results of AC conductivity were found directly related to frequency that may be due to enhanced charge storage capacity of perovskite after doping. In addition, synthesized nanoparticles exhibited excellent photocatalytic activity for the degradation of methylene blue (5 ppm). Under optimized conditions of pH, catalyst dose and UV light, 89.92% degradation of dye was achieved in 65 min. It is concluded that the synthesized nanomaterial i.e. Ba and Sr doped Lanthanum Perovskites can be a potent candidate for photocatalytic applications.

Keywords

• Perovskite
• Ba and Sr doping
• Sol-gel synthesis
• Photocatalytic activity
• Dielectric properties
• AC conductivity