Synthesis and characterization of the graphite intercalation compounds of bismuth trichloride

Abstract

The intercalation of bismuth trichloride into graphite via the vapor phase has been investigated as a function of the following parameters: temperature of the graphite, vapor pressure of the metal chloride, and pressure of chlorine. Pure-stage compounds with stage index 2, 3, and 4 are easily obtained at high pressures of chlorine (600 mbar). It was not possible to produce a stage 1 compound. With decreasing pressure of chlorine the intercalate content of the compounds becomes smaller until, at the threshold pressure of chlorine (20 mbar), no intercalation is observed anymore. All compounds were characterized by weight uptake and X-ray diffraction. In the case of the pure-stage compounds, the bismuth: chlorine ratio was determined by X-ray fluorescence as 1:3.2 ± 0.1. All compounds that were prepared at a high pressure of chlorine exhibit the same hk0 diffraction pattern. The reflections can be indexed by a rectangular in-plane lattice. The lattice constants indicate a structural relationship between the pure and the intercalated bismuth trichloride. Compounds prepared at low pressures of chlorine exhibit nonreproducible hk0 diffraction patterns.