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AC susceptibility and superconducting properties of graphene added YBa2Cu3O7-δ
journal contributionposted on 31.03.2021, 05:45 by Wei Kong, Ing Kong, MS Hamdan, S Radiman, R Abd-Shukor
© 2018, Springer Science+Business Media, LLC, part of Springer Nature. The effect of graphene (G) addition on YBa2Cu3O7−δ(G)x (x = 0 − 0.03 wt%) has been studied using the X-ray diffraction method, scanning electron microscopy, electrical resistance versus temperature, transport critical current density Jc, and AC susceptibility measurements. XRD patterns showed single-phase YBa2Cu3O7−δ (YBCO) for all samples. SEM micrographs showed filling of the voids between YBa2Cu3O7−δ grains as graphene was added. The temperature-dependent electrical resistance curves showed metallic normal state behavior and onset transition temperature Tconset between 90 and 92 K for all samples. AC susceptibility measurement showed transition temperature Tcχ′ between 90 and 93 K. Tcχ′ was maintained or improved slightly as graphene was added. The x = 0.001 wt% showed the highest Jc, i.e., 2750 A cm−2 at 77 K and 5570 mA cm−2 at 30 K which was 13 and 40 times higher than that of the non-added YBCO, respectively. The peak temperature Tp of the imaginary part of the susceptibility χ″ was around 78–82 K for all samples indicating grain coupling was not weakened as graphene was added.