Intercalation of Organic Ammonium Ions into Layered Graphite Oxide

Abstract

The intercalation of large organic ammonium ions (tetramethylammonium ions (TMA + ), tetraethylammonium ions (TEA + ), tetrapropylammonium ions (TPA + ), and tetrabutylammonium ions (TBA + )) into layered graphite oxide (GO) was systematically investigated. The intercalation reactions were completed at 25 °C after 3 days, and stable colloidal suspensions were obtained at TAAl/Hs ) 5 (molar ratio of tetraalkylammonium ions (TAA + ) over exchangeable protons in GO). The sediments after centrifuging the colloidal suspensions showed amorphous phase X-ray diffraction patterns, indicating that exfoliation of the layered structure into nanosheets took place in the suspension. When the sediments were dried at 70 °C for 3 days, layered structures of TAA + -intercalated GO materials with basal spacings of 1.56, 1.67, 1.84, and 2.37 nm, respectively, appeared. The basal spacing of the layered compounds decreased with a decrease of relative humidity during drying. When the dried TAA + -intercalated GO compounds were exposed to a humid saturated atmosphere, the basal spacing increased gradually, finally becoming an amorphous structure. The maximum saturation of intercalated TAA + ions into GO decreased with the increase in alkyl chain length. When the TAA + -intercalated materials were washed with distilled water and acid-treated, a process of deintercalation of TAA + ions from the interlayer occurred. A schematic model for the deintercalation-intercalation involving a exfoliation process is proposed. The layered structure of TAA +intercalated GO materials is discussed in terms of the dimension of the GO layer and the sizes of H2O molecules and TAA + ions.

Preparation and capacitance properties of graphene/NiAl layered double-hydroxide nanocomposite

“…1 shows the XRD patterns of the graphite, GO, as-prepared RGO, and graphene/NiAl-LDH. The diffraction peak of exfoliated GO at 11.17°(0 0 1) features a basal spacing of 0.80 nm, showing a well oxidation of graphite to the graphene oxide due to the introduction of oxygen-containing functional groups on the graphite sheets [38]. While for graphene, the peak at 11.17°o f GO completely disappears and a broad peak at around 25°rep-resenting an interlayer spacing of 0.355 nm is observed.…”

Few-layer graphene sheets with embedded gold nanoparticles for electrochemical analysis of adenine

“…31 Its position may vary from sample to sample depending on the number of layers comprising the graphene sheet. 32 Using Bragg's law, we estimated the value of the d-spacing as 0.349 nm for Gr-Au-3, 0.358 nm for Gr-Au-2, and 0.361 for Gr-Au-1. These values are in good agreement with those obtained from the analysis of edge-planes in the high resolution transmission electron microscopic images.…”

MOF–Graphite Oxide Composites: Combining the Uniqueness of Graphene Layers and Metal–Organic Frameworks

“…It has been used recently to build various nanocomposites which exhibit enhanced electronic and adsorption properties. [5][6][7][8][9][10] The graphene layers of GO are stacked together with an interlayer distance varying from 6-12 Å depending on the level of hydration. [11] Oxidation of graphite causes introduction of epoxy and hydroxyl groups to the graphene layers, as well as carboxylic groups mainly located on the edges of the layers.…”