HRTEM low dose: the unfold of the morphed graphene, from amorphous carbon to morphed graphenes

• Published in: Advanced structural and chemical imaging Vol. 2; no. 1; pp. 10 - 12
• Main Authors: Calderon, H. A., Okonkwo, A., Estrada-Guel, I., Hadjiev, V. G., Alvarez-Ramírez, F., Robles Hernández, F. C.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 22.08.2016; Springer Nature B.V; BioMed Central
• Subjects: Allotropy; Biological Microscopy; Carbon; Characterization and Evaluation of Materials; Chemistry and Materials Science; Computer simulation; Crosslinking; Damage prevention; Electron microscopy; Evolution; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Low Dose Imaging for Quantitative High Resolution and In-situ (S)TEM; Materials Science; Mechanical milling; Microscopy; Mixtures; Phases; Soot; Spectroscopy/Spectrometry; X ray photoelectron spectroscopy; Amorphous Soot; Graph Morphism; Milling Time; Graphitic Carbon; High-resolution Transmission Electron Microscopy (HRTEM)
• ISSN: 2198-0926; 2198-0926
• DOI: 10.1186/s40679-016-0024-z

We present experimental evidence under low-dose conditions transmission electron microscopy for the unfolding of the evolving changes in carbon soot during mechanical milling. The milled soot shows evolving changes as a function of the milling severity or time. Those changes are responsible for the transformation from amorphous carbon to graphenes, graphitic carbon, and highly ordered structures such as morphed graphenes, namely Rh6 and Rh6-II. The morphed graphenes are corrugated layers of carbon with cross-linked covalently nature and sp 2 - or sp 3 -type allotropes. Electron microscopy and numerical simulations are excellent complementary tools to identify those phases. Furthermore, the TEAM 05 microscope is an outstanding tool to resolve the microstructure and prevent any damage to the sample. Other characterization techniques such as XRD, Raman, and XPS fade to convey a true identification of those phases because the samples are usually blends or mixes of the mentioned phases.