Sugar coating of boron powder for efficient carbon doping of MgB2 with enhanced current-carrying performance

Two B or not two B? A liquid solution of carbohydrates, such as plain sugar, with boron powder is developed for coating boron particles with a nanoscale carbon layer. This enables the effective substitution of boron atoms by carbon and homogeneous distribution of defects in the crystal lattice of the superconductor MgB2 during the solid-state reaction. This in turn leads to significant enhancement of the material's current-carrying properties (see figure).