Utilizing the localized surface piezoelectricity of centrosymmetric Sr1-xFexTiO3 (x≤0.2) ceramics for piezocatalytic dye degradation

Centrosymmetric Sr1-xFexTiO3 (x = 0, 0.01, 0.05, 0.1, 0.2) ceramics were synthesized using solid-state reaction method. XRD confirmed the perovskite SrTiO3 phase in all samples and indicated the conversion of cubic to pseudocubic crystal symmetry with increase in Fe substitution. Raman spectroscopy showed first and second order Raman scattering modes in all samples and a new Raman mode in 691-701 cm(-1) in Fe substituted samples. The irregular morphology of grains in Sr1-xFexTiO3 (x <= 0.1) was interestingly transformed into rhombicubocta-hedron morphology in x = 0.2 sample. All samples showed significant piezocatalytic degradation of methylene blue (MB) dye. The piezocatalytic dye degradation was increased with increase in Fe substitution. The best piezocatalytic dye degradation rate of 0.00448 min(-1) was achieved in x = 0.2 sample. The localized surface piezoelectricity along with some other sono-induced phenomena might be responsible for piezocatalytic activity. The sample with x = 0.2 also showed promising MB dye degradation under visible light (k = 0.00364 min(-1)).