Synthesis and characterization of Ba₂SbNbO₆double perovskite

Full text: The double perovskites (A₂B'B''O₆) are derived from the ABO₃ perovskites when half of the octahedrally-coordinated B'cations is replaced by the suitable B" cations. They have been attracting attention due to their interesting physical properties, which can be explored for several applications, such as ferromagnetism, and magnetoresistance. The B'-O-B'' electronic interaction plays an important role in charge carriers transport. Furthermore, theoretical studies predict bandgap between 1.4 and 1.9 eV resulting in a strong sunlight absorption [1]. They also have short carriers' life, small carrier effective masses and high defect tolerance, which are favorable characteristics for photovoltaic (PV) and photocatalysis (PC) [1]. The recently proposed oxide double perovskites can potentially meet these requirements and many of the predicted A₂B'B''O₆ have not been experimentally reported [1]. The non-3d transition metal containing oxide double perovskites can be synthetized with B' site occupied by an element with 3+ valence and B" site by element with 5+ valence. Thus, this electronic structure can be tuned to exhibit both lower band gaps energy and smaller carrier effective masses which can be attractive as light harvesting for PV applications. In this context, the synthesis, processing, and electrical properties of Ba₂SbNbO₆(BSNO) double perovskite material have been examined. The BSNO samples were prepared using the solid-state reaction method and their crystal structures were confirmed using X-ray powder diffraction data along with the Rietveld method. Furthermore, the optical band gap energy and electrical properties of BSNO have been investigated to check the possibility of application in high performance solar cell. Reference 1. Sun, Q. et al. Energy Env. Sci. 12, (2018). (author)