The structural, electrical and optical properties of spark plasma sintered BaSn1-xSbxO3 ceramics

Antimony doped barium-stannate dense ceramic materials were synthesized using spark plasma sintering technique out of mechanically activated precursor powders. The influence of various Sb concentrations (x = 0.00 - 0.10) on properties of BaSn1-xSbxO3 ceramics was investigated. Relative densities of prepared samples were in the range of (79-96) %. TEM analysis revealed the presence of many dislocations in undoped BaSnO3, and their significant reduction upon doping with Sb. All samples except BaSn0.92Sb0.08O3 exhibit non-linear I-U characteristic, typical for semiconductors with potential barrier at grain boundaries. Low angle grain boundaries found only in BaSn0.92Sb0.08O3 caused the loss of potential barrier at grain boundaries which was confirmed by AC impedance spectroscopy measurements. Consequently, BaSn0.92Sb0.08O3 showed the lowest electrical resistivity and linear I-U characteristic. UV-vis analysis confirmed the increasing of band gap (Burstein-Moss shift) values in all doped samples.