Method for the modification of graphite subsurface layer to a solid mixture of SiC and graphite

We studied the interaction of molten Si and graphite surface during annealing in different atmospheres (CO, vacuum, Ar). The studies have shown that during annealing in CO atmosphere a composite material of SiC and graphite in a thick subsurface layer of the graphite is being formed, whereas at vacuum and Ar atmosphere the modified layer is either thin or absent. The composition and structure of both the composite material itself and the interface between the composite material and the graphite matrix were investigated using the methods of scanning electron microscopy and Raman spectroscopy. Studies have shown that the composite material obtained by this method has a branched fibrous structure consisting of small tubular layers of silicon carbide interspersed with large monocrystalline grains of silicon carbide of the cubic polytype, which leads to significant strengthening of the material. Thus the proposed method can be used to form a thermal protective, chemically resistant coating on graphite surface.

Nanopatterning Graphite Surface by Diazoniums Using Electrochemical Method

Molecular functionalization of graphitic surfaces with nanopatterned structures is regarded as one of the effective bottom-up techniques to tune their electronic properties towards electronics applications. Diazonium molecules have been often employed to covalently functionalize graphene and highly oriented pyrolytic graphite (HOPG) substrates. However, controlling the structure of the molecular adlayers is still challenging. In this contribution, we demonstrated an inconventional approach for covalent functionalization the HOPG surface by using mixture of 4-nitrobenzenediazonium (4-NBD) and 3,5-bis-tert-butylbenzenediazonium (3,5-TBD) molecules in which the former tends to polimezise and physisorb while the later chemically anchors on surface. The physisorbed features can be removed by washing with hot toluene and water. As a result, the HOPG surface is patterned in a quasi-periodic fashion. The efficiency of this development was verified by a combination of cyclic voltametry (CV) and atomic force microscopy (AFM) methods. This finding represents a convenient strategy for creating nanoconfined templates that might serve as nano-playgrounds for further supramolecular self-assembly and other on-surface reactions.

Insight into the Mechanisms of Low Coverage Adsorption of N-Alcohols on Single Walled Carbon Nanohorn

We report for the first time the chromatographic study of n-alcohols (from methanol to butanol) adsorption on single walled carbon nanohorn (SWCNH). Using measured temperature dependence of adsorption isotherms (373–433 K) the isosteric adsorption enthalpy is calculated and compared with the data reported for a graphite surface. It is concluded that a graphite surface is more homogeneous, and the enthalpy of adsorption on SWCNHs at zero coverage correlates well with molecular diameter and polarizability, suggesting leading role of dispersive interactions, i.e., no heteroatoms presence in the walls of SWCNH structures. Next using modern DFT approach we calculate the energy of n-alcohols interactions with a graphene sheet and with a single nanocone finally proposing a more realistic—double nanocone model. Obtained results suggest alcohols entrapping between SWCNH with OH groups located toward nanocones ends, leading to the conclusions about very promising future applications of SWCNHs in catalytic reactions with participation of n-alcohols.

Close-Stacking of Iron-Oxo-Based Double-Decker Complex on Graphite Surface Achieved High Catalytic CH4 Oxidation Activity Comparable to that of Methane Monooxygenases

<div><div><div><p>Herein, we report that the close-stacking of a double-decker-type dinuclear iron phthalocyanine complex on a graphite surface is effective for achieving high methane oxidation activity, comparable to those of certain MMOs, in an aqueous solution. </p></div></div></div>

Close-Stacking of Iron-Oxo-Based Double-Decker Complex on Graphite Surface Achieved High Catalytic CH4 Oxidation Activity Comparable to that of Methane Monooxygenases

<div><div><div><p>Herein, we report that the close-stacking of a double-decker-type dinuclear iron phthalocyanine complex on a graphite surface is effective for achieving high methane oxidation activity, comparable to those of certain MMOs, in an aqueous solution. </p></div></div></div>