X-Ray Spectral Investigation of Carbon Nanocapsule and Graphite Nanosheet Electronic Structures

Ultrasoft X-ray emission spectroscopy (USXES) was used to investigate the electronic structures of FePt alloy included carbon nanocapsules (FePt@CNCs) and graphite nanosheets (GNSs). These materials were synthesized by electric plasma discharge in an ultrasonic cavitation field of liquid ethanol. Scanning and transmission electron microscopies were used to study the spatial structures and morphologies. The electronic structure of GNSs was compared with that of reference synthetic graphite powder and high surface area reduced graphene oxide (RGO) sheets with an average thickness of one graphene layer. Investigations of the electronic structures of the FePt@CNC and GNS mixture and GNSs obtained after magnetic separation of the mixture revealed that GNS graphene layers exhibited a smaller curvature than those of carbon nanocapsules, which widened the -subband of GNSs due to overlapping of the orbitals. Thicker GNSs had a narrower CKα emission band than RGO sheets, which was related to the greater overlapping of and orbitals in the more crumpled and corrugated RGO sheets.