On the roles of graphene oxide doping for enhanced supercurrent in MgB2 based superconductors

Abstract

Due to their graphene-like properties after oxygen reduction, incorporation of graphene oxide (GO) sheets into correlated-electron materials offers a new pathway for tailoring their properties. Fabricating GO nanocomposites with polycrystalline MgB2 superconductors leads to an order of magnitude enhancement of the supercurrent at 5 K/8 T and 20 K/4 T. Herein, we introduce a novel experimental approach to overcome the formidable challenge of performing quantitative microscopy and microanalysis of such composites, so as to unveil how GO doping influences the structure and hence the material properties. Atom probe microscopy and electron microscopy were used to directly image the GO within the MgB2, and we combined these data with computational simulations to derive the property-enhancing mechanisms. Our results reveal synergetic effects of GO, namely, via localized atomic (carbon and oxygen) doping as well as texturing of the crystals, which provide both inter and intra granular flux pinning. This study opens up new insights into how low-dimensional nanostructures can be integrated into composites to modify the overall properties, using a methodology amenable to a wide range of applications.

References in corpus (22)

• Strongly Enhanced Current Densities in Superconducting Coated Conductors of YBa2Cu3O7-x + BaZrO3
• Enhancement of the critical current density and flux pinning of MgB2 superconductor by nanoparticle SiC doping
• Thin Film Magnesium Boride Superconductor with Very High Critical Current Density and Enhanced Irreversibility Field
• Systematic effects of carbon doping on the superconducting properties of Mg(B${}_{1-x}$C${}_x$)${}_2$
• Scale-free structural organization of oxygen interstitials in La2CuO4+y
• High intergrain critical current density in fine-grain (Ba0.6K0.4)Fe2As2 wires and bulks
• High Critical Current Density and Improved Irreversibility Field in Bulk MgB2 Made By A Scaleable, Nanoparticle Addition Route
• Effect of carbon nanotube doping on critical current density of MgB2 superconductor
• Significantly enhanced critical current densities in MgB2 tapes made by a scaleable, nano-carbon addition route
• Electromagnetic, atomic-structure and chemistry changes induced by Ca-doping of low-angle $YB{a}_{2}C{u}_3{O}_{7-\delta }$ grain boundaries
• Mg(B,O)2 precipitation in MgB2
• Direct observation of nm-scale Mg- and B-oxide phases at grain boundaries in MgB2
• Strong Pinning Enhancement in MgB2 Using Very Small Dy2O3 Additions
• The critical current density of advanced internal-Mg-diffusion-processed MgB2 wires
• Observation of coherent oxide precipitates in polycrystalline MgB2
• Graphene doping to enhance flux pinning and supercurrent carrying ability in magnesium diboride superconductor
• Direct observation of local K variation and its correlation to electronic inhomogeneity in (Ba1-xKx)Fe2As2 Pnictide
• Influence of the upper critical field anisotropy on the transport properties of polycrystalline MgB${}_2$
• Enhancement of the in-field Jc of MgB2 via SiCl4 doping
• Interface-driven phase separation in multifunctional materials: the case of GeMn ferromagnetic semiconductor
• Strongly Enhanced Current-Carrying Performance in MgB2 Tape Conductors by Novel C60 Doping
• Effect of oxygen incorporation on normal and superconducting properties of MgB2 films