Distribution-dependent capacitive and magnetic properties of Mn3O4 nanoparticles on reduced graphene oxide

Abstract

The composition of nanoparticles (NPs) and graphene has aroused tremendous attention because it can synergistically combine the advantages of NPs and graphene. However, manipulating the distribution of NPs and identifying the effect of the distribution of NPs on the properties of the composites remain challenges. Here, we used graphene oxide (GO) of different oxidation degrees as the platform to prepare the Mn3O4/reduce GO composites. We found that the distribution of Mn3O4 NPs could be manipulated by adjusting the oxygen content of GO. Then we investigated the effect of Mn3O4 distribution on the capacitive and magnetic properties of the composites. The results showed that the distribution of Mn3O4 NPs could change the active sites, charge transfer, uncompensated spins, and spin coupling of the composites, resulting in the distribution-dependent capacitive and magnetic properties. Especially, with discrete Mn3O4 distribution, the composites exhibited the high specific capacitance of 1626.0 F g−1 and mass magnetization of ca. 85.3 emu g−1 normalized to the portion of Mn3O4. This work will help in understanding the interaction of NPs and graphene for fundamental research, and push the way for potential capacitive and magnetic applications of graphene-based composites.