Effects on structural properties of doping zinc into Sn2Ba(Cu2−xZnx)2Oy ceramics

The study manifests the effects of different amounts of Zn doping on the structure of the nano ZnO-doped Sn₂Ba(Cu_2−xZn_x)₂O_y [x = 0.0,0.4,0.8,1.0] compounds synthesized by the solid state-reaction method. The structural changes in the produced materials have been characterized by differential thermal analysis (DTA), thermal gravimetric analysis (TGA), X-ray diffraction spectrometry (XRD), and scanning electron microscopy (SEM) methods. In the DTA analysis, while the endotherm was observed at 860 C in the pure material, the endotherms were at 810 and 880 C in the doped S10 material. The microstructure and surface morphology of pure and doped samples were analyzed using the SEM imaging method. SEM images show that the porous structure expected in Sn-based ceramics decreases and the grain size increases with the amount of Zn doping. XRD data were used to examine the crystal structures and determine the crystal phases. The effect of the ZnO dopant amount on phase transition was revealed. When the XRD peaks of the pure and doped samples are examined, it is seen that the lattice structures of both contain orthorhombic and tetragonal unit cells. It is determined Zn doping disrupts the structure of the orthorhombic 212 phase and has a positive effect on the development of the tetragonal 211 phase. It is determined that variation in the a, b, and c lattice parameters calculated using XRD data of Zn-doped materials is not monotonous. XRD analysis showed that the samples have Pmmm for the orthorhombic crystal structure and P4/mmm symmetry for the tetragonal crystal structure.