High Surface Area, sp²-Cross-Linked Three-Dimensional Graphene Monoliths

Abstract

Developing three-dimensional (3D) graphene assemblies with properties similar to those individual graphene sheets is a promising strategy for graphene-based electrodes. Typically, the synthesis of 3D graphene assemblies relies on van der Waals forces for holding the graphene sheets together, resulting in bulk properties that do not reflect those reported for individual graphene sheets. Here, we report the use of sol-gel chemistry to introduce chemical bonding between the graphene sheets and control the bulk properties of graphene-based aerogels. Adjusting synthetic parameters allows a wide range of control over surface area, pore volume, and pore size, as well as the nature of the chemical cross-links (sp(2) vs sp(3)). The bulk properties of the graphene-based aerogels represent a significant step toward realizing the properties of individual graphene sheets in a 3D assembly with surface areas approaching the theoretical value of an individual sheet.

Synthesis, toxicity, biocompatibility, and biomedical applications of graphene and graphene-related materials

“…53,54 Graphene also has excellent thermal conductivity, gas permeability, 55,56 and high surface area. [57][58][59][60] The ballistic transport 54 and the quantum hall effect 61 of graphene are also interesting features that offer immense potential for the applications of graphene-based materials. Unique features such as chemical inertness and ease of functionalization aid in the development of these materials for biomedical applications.…”

Fabrication and characterization of graphene hydrogel via hydrothermal approach as a scaffold for preliminary study of cell growth

“…Although some layering is likely to be present due to self-assembly of the graphene oxide nanosheets through van der Waals forces and hydrogen bond interactions, the graphene is disordered enough not to produce the signature π-π stacking diffraction peak. 21 The broad peaks of all the graphene hydrogel are indicative of poor ordering of graphene sheets along their stacking direction, which reflects that the three-dimensional structure is made up of a low degree of interlayer separation that mimics graphite.…”

“…Various techniques have been employed to synthesize the three-dimensional macroscale architecture, such as easy one-step hydrothermal, 15 noble metal-promoted, 16 and divalent ion-promoted 17 self-assembly of graphene oxide via hydrothermal heating of a graphene oxide and DNA mixture, 18 mixing of graphene oxide and polyvinyl alcohol, 19 dispersion of graphene oxide in triblock copolymers, 20 and curing of graphene oxide with and without the presence of resorcinol-formaldehyde suspension. 21 The resulting three-dimensional graphene macroassembly has high mechanical strength, high thermal stability, a high surface area, high water content, good electrical conductivity, good electrochemical performance, good dye-loading capacity, and self-healing properties.…”

Carbon aerogel evolution: Allotrope, graphene-inspired, and 3D-printed aerogels

“…It was determined that aerogel properties such as density, surface area, and conductivity were correlated with the RF concentration. 74 Electrical conductivities for this covalently bonded GA were as high as 1 S/cm and surface areas ranged from 500 to 1200 m 2 /g. Lim et al 75 drastically reduced the time for GA synthesis using the RF cross-linking strategy by adapting the fast gelation method developed by Mulik et al 76 The fast gelation method uses a one-pot synthesis route to prepare GO-RF gels in just a few hours instead of days.…”