Synthesis and Characterization of Acceptor Type Graphite Bi-Intercalation Compounds

Abstract

FeCl₃-based graphite bi-intercalation compounds (GBCs) were prepared from stage 5 FeCl₃-graphite intercalation compound and their formatiomechanism, stacking sequences, and lattice dynamics were studied. Bi-intercalated species were H₂SO₄, IBr, ICl, and SbCl₅. From the stacking sequences determined by X-ray diffraction measurements, bi-intercalation processes were found to be affected by the electron affinity of bi-intercalated species. Lattice dynamics of the resultant GBCs was investigated by Raman spectroscopy. In the Raman spectra of GBCs with one bi-intercalated layer, two peaks assigned as Raman active E ^{(2) i}_2g and E ^{(2) b}_2g mode frequencies were obtained, and both frequencies were affected by the bi-intercalated species. Raman spectra of GBCs with two bi-intercalated species gave two E ^{(2) b}_2g mode frequencies due to the double-intercalate coupling effect.