A Comprehensive Study of Bulk Nd1-xSrxNiO2: Understanding the Absence of Superconductivity

This study investigates the absence of superconductivity in bulk type nickelate and analyzes the structural and transport characteristics of the materials. Infinite layer bulk type Nd 1-x Sr x NiO 2 with Sr doping level x for 0.0, 0.1 and 0.2 are synthesized by conventional solid state synthesis method. The crystallographic structure Nd 1-x Sr x NiO 2 of is found to be stable for different doping levels using X-ray diffraction (XRD) analysis and confirms phase purity. Scanning electron microscopy (SEM) analysis reveals the grain morphology and indicates the absence of notable microstructural features that support superconductivity. The nature of grain size distribution of Nd 1-x Sr x NiO 2 , with x = 0.0, 0.1 and 0.2 are analyzed. The transport measurement of prepared bulk type nickelate samples are performed by four probe technique with the help of closed cycle cryogenerator. The electrical transport characteristics based on 3D Variable Range Hopping (VRH) conduction models are examined. This study presents the alternative synthesis techniques to stabilize the superconducting phase and an overall insight into the causes for the failure of superconductivity.