”Eau de graphene” from a KC₈ graphite intercalation compound prepared by a simple mixing of graphite and molten potassium

Abstract

We synthesized KC8 by simply mixing molten potassium and graphite at 180 °C under inert atmosphere. The KC8 shows typical shiny bronze color, Raman characteristics and XRD pattern of an efficiently intercalated stage 1 GIC, and is of sufficient quality to produce fully exfoliated graphenide solutions in tetrahydrofuran (THF) and subsequently single layer graphene in water as ”eau de graphene” (EdG). The evolution of absorption and Raman spectroscopic signatures of the EdG as a function of processing conditions give key indications on the number of layers of the graphene flakes dispersed in EdG. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)

Accessing Low-Valent Titanium CCC-NHC Complexes: Toward Nitrogen Fixation

“…Illustrated in Figure 4A (no-D THF) are the characteristic signals for identifying trichloro complex 2 by its triplets H c and H d at δ 4.33 and at δ 0.84. To attempt nitrogen fixation by low oxidation states of Ti exclusively, stoichiometric reduction reactions of complex 2 were executed with one-and two-fold molar excesses of freshly prepared KC 8 as follows [53]. A homogeneous solution of compound 2 in an NMR tube, was sonicated with equimolar ratio of KC 8 in THF at ambient temperature under inert conditions ( Figure 4B).…”

“…Paramagnetic broadening of all (triplets H c and H d at δ 4.33 and at δ 0.84) major peaks in a no-D 1 H NMR analysis of the solution was consistent with reduction in both the cases ( Figure 4B, Figures S7 and S9). executed with one-and two-fold molar excesses of freshly prepared KC8 as follows [53]. A homogeneous solution of compound 2 in an NMR tube, was sonicated with equimolar ratio of KC8 in THF at ambient temperature under inert conditions ( Figure 4B).…”

Oxo‐Functionalized Graphene: A Versatile Precursor for Alkylated Graphene Sheets by Reductive Functionalization

“…After both charged materials were exposed to hexyl iodide, the products were purified in a separation funnel and filtered under vacuum. The direct bulk functionalization of graphite or corresponding KC 8 , respectively, leads only to minor amounts of single layers and mainly fractions of multilayered graphene sheets (hexyl‐G ≥1 GIC ) . A partial individualization of hexyl‐G 1 /SCH was possible by the use of o ‐dichlorobenzene and mild ultrasonication (Figure S1 C in the Supporting Information), but not in sodium cholate solution or with other common organic solvents such as NMP, CHP, cyclohexane, or THF.…”

“…After exposure to strong reducing agents, the stacked and negatively charged graphenide sheets can be functionalized by suitable electrophiles such as alkyl or aryl halides as well as iodonium or diazonium cations ,. However, as the complete exfoliation of the material down to the monolayer still cannot be fully controlled, few‐layer functionalization is a competing process and thus, the yield of functionalized G 1 is limited ,…”

Anchoring conductive polymeric monomers on single-walled carbon nanotubes: towards covalently linked nanocomposites

“…The potassium salt of SWCNTs was prepared by reacting potassium with SWCNT powder on a hot plate, under an inert argon-filled glovebox environment as has been reported before for nanotubes and for graphite intercalation. [25,31,32] Stoichiometry was chosen as KC10 to have a sufficiently high functionalization upon later exposure to the monomers BTI, BATI and BPI. [33] In a typical reaction, 50 mg of freshly cut potassium metal was added to a 20 mL glass vial containing a 150 mg SWCNT sample.…”