Manchester Centre for Mesoscience & Nanotechnology, University of Manchester, Manchester M13 9PL, United Kingdom.
Phys Rev Lett. 2010 Nov 12;105(20):207205. doi: 10.1103/PhysRevLett.105.207205.
We have studied magnetization of graphene nanocrystals obtained by sonic exfoliation of graphite. No ferromagnetism is detected at any temperature down to 2 K. Neither do we find strong paramagnetism expected due to the massive amount of edge defects. Rather, graphene is strongly diamagnetic, similar to graphite. Our nanocrystals exhibit only a weak paramagnetic contribution noticeable below 50 K. The measurements yield a single species of defects responsible for the paramagnetism, with approximately one magnetic moment per typical graphene crystallite.
我们研究了通过石墨超声剥离获得的石墨烯纳米晶体的磁化。在 2 K 以下的任何温度下都没有检测到铁磁性。我们也没有发现由于大量边缘缺陷而预期的强顺磁性。相反，石墨烯是强抗磁性的，类似于石墨。我们的纳米晶体仅表现出微弱的顺磁贡献，在 50 K 以下即可察觉。测量结果表明，只有一种缺陷物种对顺磁性负责，每个典型的石墨烯微晶大约有一个磁矩。
