Significant enhancement of critical current density in Gly-doped MgB2 bulk by tailoring the formation of MgO

A significant enhancement of critical current density (J c) was obtained in MgB2 +3wt.% glycine samples with a large amount of MgO. The improvements in J c and in the irreversible magnetic field (H irr) are attributed to the pinning effects of high C-substitution level, nanoscale MgO, and to the even boundaries of small grains. This doping method overcomes the degradation of J c under a low field in previously reported SiC-doped samples. Moreover, the formation of MgO was demonstrated to be the result of the reactions between Mg, CO2 and O2. [ABSTRACT FROM AUTHOR]