Positive effect of co-addition of Dy₂O₃/Ag and Dy₂O₃/WO₃ nanoparticles on the physical critical parameters and electrical transport properties of YBCO ceramic

In this study, YBa₂Cu₃O_7−δ (YBCO) polycrystalline samples with co-addition of nanostructure materials (NSMs) of 0.1 wt% Dy₂O₃/Ag and 0.1 wt% Dy₂O₃/WO₃ were synthesized via solid-state reaction sintering. Herein, the considered NSMs are of two shapes: nanoparticles (NPs) of dysprosium oxide and silver and nanowires of tungsten oxide. X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) were used to examine the structure and morphology of samples. Resistivity versus temperature (ρ(T)), ac susceptibility (χ(T)), and dc magnetization (M(H)) measurements have been carried out on superconducting YBCO to deduce critical superconducting parameters like B_c1 and J_c. Using the Aslamazov-Larkin approach, the induced excess conductivity analysis was performed to complete values of critical lengths such as ξ_co, λ_o, critical magnetic fields (B_c1, B_c2), and critical current density J_c at 0 K. The combined addition of Dy₂O₃/Ag and Dy₂O₃/WO₃ conserves the orthorhombic structure, the grain size of about some micrometers, and the volume fraction of superconductor grain (V_sg%). NSMs co-addition ameliorates the assembly of grains and their connectivity to empower the carriers' charge transportation between the grains. Dy-rich entities are inserted into the YBCO grains' surfaces. The critical superconducting parameters B_co, B_c1, B_c2, and J_c are high in co-added samples due to the decrease in intergrain resistivity and the better competence of trapping flux lines inside the samples. The combination of different types of NSMs inside YBCO constitutes a hopeful way to compromise between better grain coupling and higher flux pinning. Ag NPs coupled with Dy₂O₃ NPs act more efficiently than WO₃NW coupled with Dy₂O₃ NPs in YBCO compounds to make its properties better.