Rh nanoparticles in a graphite lattice have been prepared by reduction of a RhCl 3 -graphite intercalation compound by hydrogen gas at high temperatures (I) or at room temperature by Li-diphenylide (II). In all cases, the reduction was complete. All four samples (natural graphite and HOPG) showed a full set of fcc Rh reflections by selected-area electron diffraction. This indicates a particle thickness from at least four layers. Only in the case of the samples reduced by (II) can additional very strong reflections can be observed. They seem to be due to the occurrence of 2D Rh structures with (2 × a graphite ) and (3 × a graphite ) superstructures. For a (2 × a graphite ) Rh superstructure on graphite or expanded multilayers of fcc Rh, an induced magnetic moment was theoretically predicted. Bright-field electron microscopy shows particles in the size ranges 11-106 nm (I) and 1.5-37.5 nm (II). The magnetism of Rh-Gr is related to the detail of Rh nanoparticles and nanographites, depending on the condition of reduction. Short-range magnetic order is observed in Rh nanoparticles for the sample with uncommon spacings. However, Curie-like susceptibility is observed at low temperatures for all samples. This is due to nanographites with zigzag edges. As reference substances, Rh nanoparticles were generated in bentonite and on kaolin by polyol reduction of Rh-acetate hydrate. The size range in bentonite was 2.1-60 nm; the kaolin samples showed Rh particles from 5.3-52.5 nm. Electron diffraction patterns gave no evidence of an expanded lattice in those Rh particles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.