Amorphous state of sp² solid carbon

Abstract

Two-mode valence electron configuration of carbon atoms lays the foundation of the unique two-mode amorphous state of the monoatomic carbon solid. From the fundamentals of solid-state physics, sp 3 and sp 2 amorphous carbons are two different amorphous species characterized by conceptually different short-range orders, namely, groups of tetrahedrally bonded sp 3 configured atoms and nanoscale size-restricted sp 2 graphene domains framed with heteroatom necklaces. Molecular character of sp 2 amorphics is coherent with the reaction mechanism of the solid amorphicity in due course of the enforced fragmentation.

Sorption Properties of Activated Carbons for the Capture of Methyl Iodide in the Context of Nuclear Industry

“…S4 (A)). This carbon speciation is in agreement with the obtained broad XRD patterns for the studied AC (not shown here) typical of amorphous carbon structure [24,25].…”

Graphene Domain Signature of Raman Spectra of sp2 Amorphous Carbons

“…Long-time and numerous studies of amorphous solids have led researchers to the conclusion that a confident interpretation of their Raman spectra is inseparable from the consideration of the nature and type of the solids amorphization. Previous structural and analytical studies of amorphous carbons were analyzed from this viewpoint, in course of which it was subsequently established that the solids should be attributed to molecular amorphics of a new type of amorphicity, which can be called the enforced fragmentation of honeycomb canvas [19]. Chemical reactions occurring at the fragment edges are suggested to be one of the most important causes of the fragmentation stabilization.…”

Lateral Structured Phototransistor Based on Mesoscopic Graphene/Perovskite Heterojunctions

“…The graphene edges can also be testified by the Raman spectra in Figure 1 b. Since the D peak (~1350 cm −1 ) requires a defect for its activation and the G peak (1580 cm −1 ) corresponds to the doubly degenerate zone center E 2g mode, we can see that, the longer the growth time of GNWs used, the larger the intensity ratio of the D to G (I D /I G ), which means more graphene edge defects and a higher degree of disorder shaped [ 30 , 31 ]. However, from the increasing intensity of the D peak and the increasing full width at half maximum (FWHM) of the 2D peak, it could be inferred that a longer growth time leads graphene nanosheets to nanocrystalline graphite.…”