Polyhydroxylated few layer graphene for the preparation of flexible conductive carbon paper

Abstract

Electrically conductive flexible carbon papers were prepared, based on hydroxyl functionalized few layer graphene (G-OH). G-OH was obtained from the reaction of KOH with nanosized graphite with a very high surface area (HSAG), greater than 300 m2 g-1, and with high shape anisotropy, with the help of mechanical and thermal energy. Wide angle X-ray and Raman analyses showed that the core of G-OH had the structure of infinite and ideal graphene layers and that the interlayer distance between the few stacked graphene layers was the same as in pristine HSAG. Hydroxyl groups were thus essentially located in peripheral positions. High resolution transmission electron microscopy revealed the presence of graphene aggregates made by a number of layers as low as 6. Stable water suspensions were obtained, with concentrations up to 4 mg mL-1. Mild centrifugation of such suspensions had interesting efficiency as a method for producing few layer graphene: about 35% by mass of pristine HSAG was isolated as few layer graphene from supernatant suspensions. Flexible and electrically conductive carbon papers were prepared by coating a paper support with a G-OH water suspension. This work demonstrates that carbon papers can be prepared without adopting the traditional oxidation-reduction procedure, avoiding harsh reaction conditions, dangerous and toxic reagents, solvents and catalysts

FACILE FUNCTIONALIZATION OF sp2 CARBON ALLOTROPES WITH A BIOBASED JANUS MOLECULE

“…The width at half height, b hk' ¼ (B hk' À b) was corrected, for each observed reflection with b hk' , 18, by subtracting the instrumental broadening of the closest silicon reflection from the experimental width at half height, B hk' . 75 UV-Vis Spectroscopy. -The suspensions of adduct (3 mL) were placed by pipette Pasteur, in quartz cuvettes of 1 cm optical path (volume 1 or 3 mL) and analyzed by a spectrophotometer Hewlett Packard (Palo Alto, CA, USA) 8452A Diode Array Spectrophotometer.…”

Facile and sustainable functionalization of graphene layers with pyrrole compounds

“…Further characterization has been reported elsewhere. The lateral size of graphitic layers was observed in TEM micrographs to be in the range from about 300 nm to more than 1 micron [23]. The number of layers stacked in crystalline domain was calculated, from XRPD, to be about 35 [23,53].…”

“…The polymeric nature of graphene layer with the six atoms aromatic ring as the repeating unit is responsible for such exceptional properties. Hence, main objectives of graphene synthesis [8][9][10][11][12] and functionalization [8,[13][14][15][16][17][18][19][20][21][22][23] are to obtain and preserve such structure.…”

Graphene‐Based Carbocatalysts for Thermoset Polymers and for Diastereoselective and Enantioselective Organic Synthesis

“…Graphite oxide is obtained from graphite by strong oxidation procedures, such as, for example, the Hummers method, whereas graphene oxide is obtained by ball‐milling exfoliation of graphite oxide. Detailed characterization of HSAG by many techniques (mainly elemental analysis, high‐resolution X‐ray photoelectron spectroscopy and Raman spectroscopy) has been reported in recent papers …”

“…Graphite oxide is obtained from graphite by strong oxidation procedures, such as, for example, the Hummers method, whereas graphene oxide is obtained by ball-milling exfoliation of graphiteo xide.D etailedc haracterizationo fH SAG by many techniques (mainly elemental analysis,h igh-resolutionX -ray photoelectron spectroscopy and Raman spectroscopy) has been reportedi nr ecent papers. [36,37] The wide-angle X-ray diffraction (WAXD) patterns of at ypical HSAG ( Figure 1a)s how an interlayer distance of 0.34 nm. The WAXD patterns of derived graphite oxide show an increasei n the interlayer distance from 0.34 nm up to values generally in the 0.75-0.85 nm range (0.84 nm fort he sample in Figure 1b, with aO /C weight ratio closet o0 .7).…”