The simple synthesis of ultralow-density (≈2.32 mg cm-3) 3D reduced graphene oxide (rGO) aerogels that exhibit high electrical conductivity and excellent compressibility are described herein. Aerogels are synthesized using a combined hydrothermal and thermal annealing method in which hexamethylenetetramine is employed as a reducer, nitrogen source, and graphene dispersion stabilizer. The N-binding configurations of rGO aerogels increase dramatically, as evidenced by the change in pyridinic-N/quaternary-N ratio. The conductivity of this graphene aerogel is ≈11.74 S m-1 at zero strain, whereas the conductivity at a compressive strain of ≈80% is ≈704.23 S m-1, which is the largest electrical conductivity reported so far in any 3D sponge-like low-density carbon material. In addition, the aerogel has excellent hydrophobicity (with a water contact angle of 137.4) as well as selective absorption for organic solvents and oils. The compressive modulus (94.5 kPa; ρ ≈ 2.32 mg cm-3) of the rGO aerogel is higher than that of other carbon-based aerogels. The physical and chemical properties (such as high conductivity, elasticity, high surface area, open pore structure, and chemical stability) of the aerogel suggest that it is a viable candidate for the use in energy storage, electrodes for fuel cells, photocatalysis, environmental protection, energy absorption, and sensing applications.
Bibliographical noteFunding Information:
This research was supported by the MSIP (Ministry of Science, ICT, and Future Planning), Korea, under the "IT Consilience Creative Program" (IITP-2015-R0346-15-1008) supervised by the IITP (Institute for Information and Communications Technology Promotion). This research was also supported by a grant from the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2013R1A1A2012111).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics