Over the history of carbon, it is generally acknowledged that Bernal AB stacking of the sp2 carbon layers is the unique crystalline form of graphite. The universal graphite structure is synthesized at 2,600~3,000 °C and exhibits a micro-polycrystalline feature. In this paper, we provide evidence for a metastable form of graphite with an AA' structure. The non-Bernal AA' allotrope of graphite is...

Lithium evaporation treatments in the National Spherical Torus Experiment (NSTX) have shown dramatic improvements in plasma performance increasing the viability of lithium as a Plasma Facing Component (PFC) material. In order to understand the complex system of lithiated ATJ graphite, chemical sputtering measurements of plain and lithiated ATJ graphite are conducted in our upgraded IIAX (Ion Su...

The basal plane cleavage energy (CE) of graphite is a key material parameter for understanding many of the unusual properties of graphite, graphene and carbon nanotubes. Nonetheless, a wide range of values for the CE has been reported and no consensus has yet emerged. Here we report the first direct, accurate experimental measurement of the CE of graphite using a novel method based on the self-...

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 8103 wileyonlinelibrary.com High performance cathodes, including metal oxides,[11–14] phosphates,[15–18] hexacyanometalates,[19–21] sulfur,[22,23] metal sulfides,[24,25] and organic materials,[26–28] have been reported, and porous carbonaceous materials and metallic Sb and Sn anodes also show high capacity and long cycling stability.[29–34] In c...

The different shot peening responds of a grey cast iron (GI) with its flake graphite and a compacted cast iron (CGI) with its vermicular graphite was analyzed and compared in this paper. For peening using identical parameters, CGI showed a larger plastic deformation zone with higher subsurface compressive stresses than GI. Electron backscatter diffraction (EBSD) mapping and backscatter electron...

Self-lubricating polymer compounds are currently used for a wide range of applications such as bearings, gears, and water meters. Under severe conditions such as high pressure, high velocity, and/or high temperatures, the material fails (PV limit). In this study, we investigated the effect of graphite on the tribological properties of polystyrene (PS) with “ball-on-three-plates” tests. Graphite...

Abundant graphite particles occur in amphibolite-grade quartzite of the Archean-Paleoproterozoic Wutai Metamorphic Complex in the Wutaishan area of North China. Petrographic thin section observations suggest that the graphite particles occur within and between quartzite clasts and are heterogeneous in origin. Using HF maceration techniques, the Wutai graphite particles were extracted for furthe...

Despite numerous studies presenting advances in tomographic imaging and analysis of lithium ion batteries, graphite-based anodes have received little attention. Weak X-ray attenuation of graphite and, as a result, poor contrast between graphite and the other carbon-based components in an electrode pore space renders data analysis challenging. Here we demonstrate operando tomography of weakly at...

The interface between skin and electrodes plays a major role in the accuracy efficiency of biopotential measurements. For reliable biosignal recording, stable low-impedance contact is required target tissue. Conventional wet (Ag/AgCl) are composed metal with skin-adhesive hydrogel. However, for long-term measurement, direct pre-gel electrode causes discomfort irritation, especially infants peop...

A homologous series of propylene carbonate (PC) analog solvents with increasing length of linear alkyl substitutes were synthesized and used as co-solvents with PC for graphite-based lithium-ion half cells. A graphite anode reaches a capacity of around 310 mAh/g in PC and its analog co-solvents, with 99.95 percent Coulombic efficiency, similar to the values obtained with ethylene carbonate-base...