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The superdense lithium-graphite intercalation compound (GIC), LiC 2 , first synthesized by the author was prepared by the original technique in a piston-cylinder high-pressure chamber with internal heater. Cleaved surfaces of this compound, LiC 3 , LiC 6 and pristine graphite were studied by the X-ray photoelectron spectroscopy (XPS) technique. It was shown that chemical shifts of carbon do not vary in the range LiC 6 to LiC 2 which suggests that the additional lithium intercalation into LiC 6 gives no significant change in the charge transfer rate per carbon atom. Carbon/lithium atom ratios were obtained for freshly cleaved surfaces and for the surfaces after argon ion bombardment. It was shown that the bombardment results in the surface decomposition of LiC 2 -GIC.

Intercalation of potassium superoxide KO 2 into graphite in the presence of potassium metal was studied. Graphite intercalation compounds of stage 1 (assigned formula C 4 KO 2 , c -axis repeat distance 8.44 A) and stage 2 (assigned formula C 8 KO 2 , c -axis repeat distance 11.75 A) were synthesized and isolated for the first time. A quadruple intercalate layer KOOK is supposed. In-plane structure of the intercalate layer is discussed mostly on the basis of X-ray diffraction intensity analysis and transmission electron microscopy electron diffraction. A metal-like temperature dependence of c -axis resistivity was obtained in the 1.5–300 K temperature range where the resistivity values at room temperature are 0.07 and 0.81 Ω cm for stage-1 and stage-2 compounds, respectively. The results of magnetic susceptibility measurements suggest that the oxygen species are in nonmagnetic states.

A model for the constitution of graphite intercalation compounds has been proposed. The model is based on the assumption that intercalant particles may be considered as elastic balls squeezed by elastic graphitic networks. Stability limits (minimum pressure of existence) and compressibilities were calculated for a large number of donor intercalation compounds. Agreement with experimental data is excellent. Stability limits of some non-discovered compounds and several compressibilities have been predicted. In particular, the calculated compressibility of recently discovered C2Na is 11 × 10−12 Pa−1. The possibility of applying this model to acceptor compounds and higher stage compounds has been discussed.

We present here an experimental study of ITO/Polyaklythiophene(PAT)/C 60 /Al photovoltaic cells. We found that efficiency of the cells can be substantially improved by introduction of hole collecting layer between PAT and ITO or electron transporting layer between PAT and C 60 . A discussion of the results in terms of energy band diagrams follows experimental data.

Graphite intercalation compounds (GICs) with heavy alkali oxides were studied by X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). It is shown that both Cls and Ols spectra of CsOx GICs are essentially different from that of the oxidized surfaces of Cs GICs. It is found that the surface areas of CsOx GICs are enriched with oxygen due to migration of the oxygen from the bulk. A number of hexagonal and square superlattices were observed in the STM images of CsOx GICs. Square 4×4A2 superlattice was observed at the surface of KOX GICs.

Low-temperature magnetoresistance measurements on pristine bundles revealed non-oscillatory magnetoresistance behavior comprising positive and negative components. However, upon intercalation of K-atoms, random oscillations about a large negative underlying trend were revealed—features that were also seen for some pristine bundles taken from the same source material. When plotted as magneto-conductance, the amplitude of these oscillations is comparable to that of the ‘universal’ conductance fluctuations recently observed for a single multiwall nanotube [Langer, L. et al, Phys. Rev. Lett. 76 (1996) 479]. This amplitude is temperature-independent below T c ∼3 K. An explanation of these observations is given within the framework of 3D weak localization theory.

We report the first observation of intercalation into carbon nanotubes without breaking the tubular structure. Both K-intercalated and FeCl 3 -intercalated tubes were produced by a gas-phase reaction of oriented multiwall “buckybundle” material with potassium metal and iron (III) chloride, respectively. The resulting material preserves its oriented structure. It has been studied by X-ray diffraction, SEM, weight uptake and magnetoresistance measurement techniques. Interlayer spacing in the intercalated tubes is very close to that in corresponding graphite intercalation compounds. It has been shown that intercalated buckybundles exhibit some noteworthy galvanomagnetic properties including the random conductance fluctuations. The intercalation process is accompanied by swelling of the tubes. The swollen sections alternate non-intercalated “necks” forming an impressive “bead-line” pattern.