Improved flux pinning properties of Graphene Oxide blended La1.85Sr0.15CuO4 (LSCO) superconductor

Abstract

In this study, the effect of blending various concentrations of Graphene Oxide (GO) on the structural, electrical, magnetic and flux pinning properties of the La_1.85Sr_0.15CuO₄ (LSCO) superconductor is reported. LSCO + x wt. % GO (x = 0.0,0.1,0.3,0.5,1.0) composites have been prepared using the solid-state reaction route. XRD analysis shows that the tetragonal crystal structure of LSCO is unaffected in the composites. It has been observed that the critical temperature ($T_c^{zero}$) is reduced rapidly with increasing concentration of GO. The critical current density ($J_c$) and pinning force density ($F_p$) are enhanced for the LSCO-GO composites compared to pure LSCO, which is attributed to the creation of artificial pinning centres due to the addition of GO. The enhancement in $J_c$ (∼1.91 times) and $F_p$ (∼2.67 times) at 5 K has been found maximum for the 0.3 wt % GO-added composite. The nature of pinning in the samples has been probed using $F_p\left(H\right)$ data.