Graphene reactivity

When the electrolyte solutions are not too reactive, as in the case of ethereal solutions, there is no massive formation of protective surface films at potentials above Li intercalation potential, and most of the solvent reduction processes may occur at potentials lower than 0.3 V vs. Li/Li+. Hence, the passivation of the electrodes is not sufficient to prevent cointercalation of solvent molecules. This leads to an exfoliation of the graphite particles into amorphous dust (expholiated graphene planes). This scenario is demonstrated in Figure 2a as the reduction of the 002 diffraction peak21 of the graphite electrode, polarized cathodically in an ethereal solution. 

It has been known that the basal graphite plane (graphene hexagon) is chemically inert. However, CNTs are susceptive to some chemical reactions due to the it-orbital mismatch in the curvature structures. Oxidation studies have revealed that the tips (caps) of CNTs are more reactive than the cylindrical parts [8, 20], Ab initio calculations indicate that the average charge density of a pentagon (at the tips) is 3 4 times larger... 

R. Sharma, J. H. Baik, C. J. Perera, M. S. Strano, Anomalously large reactivity of single graphene layers and edges toward electron transfer chemistries, Nano Lett., vol. 10, pp. 398-405, 2010. 

S. M. Dubois, A. Lopez-Bezanilla, A. Cresti, F. Triozon, B. Biel, J.-C. Charlier, S. Roche, Quantum transport in graphene nanoribbons Effects of edge reconstruction and chemical reactivity, ACS Nano, vol. 4, pp. 1971-1976, 2010. 

Wang, Q.H.,etal., Understanding and controlling the substrate effect on graphene electron-transfer chemistry via reactivity imprint lithography. Nature Chemistry, 2012. 4(9) p. 724-732. 

This arrangement changes drastically after inspection of the etched sample. The deep large voids designate the areas of isotropic phase (see Fig. 9.1 phase (b)). It further highlights that the anisotropic well-crystallized graphene layers adhere strongly only in a thin rim around the fiber axis. The immediate interface is also quite reactive to... 

Figure 9.5(d) gives an impression about the topo-chemical nature of the hydrogen atom s attack on carbon. Even these highly reactive species attack carbon not in an isotropic form but react from the edges and thus decorate, after some extent of conversion, the planar shape of the BSU as stacks of graphene layers with uneven but identical outer shapes. The rounded protrusions into the edge structure arise from defect clusters that would manifest themselves in a perpendicular view as etch pits . 

Petit C, Mendoza B, Bandosz TJ. Reactive adsorption of ammonia on Cu-based MOF/graphene composites, Langmuir 26 (2010) 15302-15309. 

Seredych M, Mabayoje 0, Bandosz TJ. Interactions of N02 with zinc (hydr)oxide/graphene phase composites Visible light enhanced surface reactivity,/. Phys. Chem. C 2012,... 

Seredych M, Mabayoje 0, and Bandosz TJ. Role of water splitting in visible light enhanced reactive adsorption ofS02 on composites of Zinc(Oxy)Hydroxide with Graphite Oxide and Graphene, Adv. Funct. Mater., submitted... 

Contrarily to the basal plane, the prismatic edges terminating the graphene layers as well as defects in the basal plane are highly reactive and usually saturated, with H, 0, or N atoms being the key players in most of the catalytic applications of carbon materials (see Chapter 19). The abundance of groups illustrated in Fig. 15.5 is well known from organic chemistry. These functionalities define the acidity/basicity and also the hydrophilic character of the nanocarbons. 

Fig. 19.10 Illustration of the fate of a vacancy in a reactive atmosphere front and side view of optimized geometry of graphene C49H1802 (M = 3).

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