Polycrystalline YBa 2 Cu 3 O 7 − δ is a highly promising material for bulk superconductivity. It can be doped with a suitable element to enhance its superconducting properties. In this study, polycrystalline YBa 2 Cu 3 O 7 − δ was added with Ag 2 O nanoparticles and the effects on electrical conductivity and microhardness properties were investigated. The amount of Ag 2 O nanoparticles ( 2 Cu 3 O 7 − δ powder (∼50 nm) using solid state reaction. The mixture was pelletized and sintered at 950 °C for 1 h The resultant FTIR curves indicated the existence of Ag 2 O as the strongest peak representing YBa 2 Cu 3 O 7 − δ at around 1468 cm −1 was shifted to 1451 cm −1 , the vibration modes of Ag-O. For the composition with more than 3.0 wt. % Ag 2 O, the XRD analysis revealed that the incorporation of Ag into YBa 2 Cu 3 O 7 − δ structure altered the orthorhombicity of the samples. The presence of Ag in YBa 2 Cu 3 O 7-δ in each sample was further confirmed by EDX analysis. From the SEM images, the Ag 2 O nanoparticles were observed to be distributed in the YBa 2 Cu 3 O 7 − δ grain-boundaries in samples with 3.0 wt. % Ag 2 O and less. The agglomeration of Ag 2 O nanoparticles was observed for the samples with more than 3.0 wt. % Ag 2 O. The electrical conductivity as measured using Van Der Pauw method at room temperature, improved as the Ag 2 O amount was increased above 1.0 wt. %. In term of the superconducting properties, T C of samples with ≤ 3.0 wt. % Ag 2 O slightly exceeds the T C of pure YBa 2 Cu 3 O 7 − δ . The T C is significantly reduced by ∼10 K as the Ag 2 O amount is increased beyond 3.0 wt. % to 9.0 wt. %. The hardness of Ag 2 O added YBa 2 Cu 3 O 7 − δ increases with the addition of Ag 2 O but decreases as the amount exceeds 3.0 wt. % due to the agglomeration of Ag 2 O nanoparticles.
