The effect of reduced graphene oxide addition on the superconductivity of MgB2

Reduced graphene oxide (rGO) and highly reduced chemically converted graphene (rCCG) samples were prepared under different processing conditions and were doped into MgB2 by a diffusion process at 800 °C for 10 hours. It was demonstrated that a small addition rCCG can significantly improve the superconducting properties of MgB2. Doping of MgB2 with 1 mol% of rCCG resulted in a Jc of 5.45 × 105 A cm−2 at 20 K in self-fields, which is nearly 32% improvement over that of the undoped sample. This is a significant improvement as most carbon sources adversely affect the Jc performance at the zero field.