Premium
Preparation and Characterization of Graphene Oxide Aerogels: Exploring the Limits of Supercritical CO 2 Fabrication Methods
Author(s) -
Borrás Alejandro,
Gonçalves Gil,
Marbán Gregorio,
Sandoval Stefania,
Pinto Susana,
Marques Paula A. A. P.,
Fraile Julio,
Tobias Gerard,
LópezPeriago Ana M.,
Domingo Concepción
Publication year - 2018
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201803368
Subject(s) - aerogel , graphene , supercritical fluid , materials science , supercritical carbon dioxide , mesoporous material , oxide , chemical engineering , surface modification , fabrication , characterization (materials science) , nanotechnology , supercritical drying , environmentally friendly , specific surface area , catalysis , organic chemistry , chemistry , medicine , alternative medicine , ecology , biology , engineering , pathology , metallurgy
The supercritical carbon dioxide (scCO 2 ) synthesis of non‐reduced graphene oxide (GO) aerogels from dispersions of GO in ethanol is here reported as a low‐cost, efficient, and environmentally friendly process. The preparation is carried out under the mild conditions of 333 K and 20 MPa. The high aspect ratio of the used GO sheets (ca. 30 μm lateral dimensions) allowed the preparation of aerogel monoliths by simultaneous scCO 2 gelation and drying. Solid‐state characterization results indicate that a thermally‐stable mesoporous non‐reduced GO aerogel was obtained by using the supercritical procedure, keeping most of the surface oxygenated groups on the GO sheets, thus, facilitating further functionalization. Moreover, the monoliths have a very low density, high specific surface area, and excellent mechanical integrity; characteristics which rival those of most light‐weight reduced graphene aerogels reported in the literature.