Synthesis and crystal structure of a new bismuth tin titanate with the pyrochlore-type structure

A pyrochlore-type compound, Sn0.34Bi1.52Ti1.86Sn0.14O6.62, was synthesized using a solid-state reaction in a N2 atmosphere. The crystal structure was refined using the synchrotron powder X-ray diffraction data. This compound comprised mixed-valence states Sn2+ and Sn4+. The morphology of this compound was irregular shapes with particle size approximately 1–5 µm. The band gap of this compound was estimated to be 2.83 eV from the ultraviolet–visible spectrum. The dielectric constant of this compound was 78 under 100 Hz frequency and weak photocatalytic activity for methylene blue degradation under visible light irradiation.