Graphite structure with correlated graphine layers has high 3-D crystalline order. A 2-D honeycomb structure of uncorrelated graphene layers is called turbostratic carbon. There is no interlayer site correlation between adjacent graphene planes.
Physical−chemical transitions occur as charring temperature increases resulting in four distinct categories of char: (i) transition chars, the crystalline character of the precursor materials is preserved; (ii) amorphous chars, the heat-altered molecules and incipient aromatic polycondensates are randomly mixed; (iii) composite chars: poorly ordered graphene stacks embedded in amorphous phases; and (iv) turbostratic chars dominated by disordered graphitic crystallites.
Schematic diagrams exhibiting (a) a 3-D graphite lattice (b) a turbostratic structure, and (c) a schematic structural model of the outer two layers for a multiwall carbon nanotube. The electronic structure of turbostratic graphite, a zero-gap semiconductor, is qualitatively different from that of ideal graphite, a semimetal. Crystalline disorder and interlayer spacing introduces an effective energy gap.
Groundwater with a source of organic carbon or other electron donors shows a sequence of distinct redox zones along flowpaths. Similar patterns can be seen along upward flowpaths in discharge areas in organic-rich wetland and bottom sediments. Evaluating Nutrient Fate and Redox Controls in Groundwater in Riparian Areas - USGS Water Resources of Maryland, Delaware, and D.C. Area (WRD MD-DE-DC)
In single crystal graphite (top), the carbon atoms are bonded in hexagonal arrays that are stacked in ordered layers. Turbostratic carbon (bottom), however, has disordered stacking through random rotation or displacement of ordered layers. This disordered structure is what gives pyrolytic turbostratic carbon its unique mechanical properties.