Possible Ferromagnetism of a Nitrogen-Doped Carbon Material

A nitrogen-doped carbon material (NDCM) is synthesized by grinding a graphene oxide–melamine mixture in a planetary mill in which the balls and the body are both made of zirconium dioxide. In addition to a narrow signal at g = 2.0034, the EPR spectrum of the NDCM exhibits a broad signal at g = 2.08. Studies with a magnetometer show the NDCM is presumably a ferromagnetic material with a saturation magnetization at room temperature of approximately 0.02 emu/g and a coercive force of 100 Oe.