Effect of graphene oxide size and structure on synthesis and optoelectronic properties of hybrid graphene oxide‐poly(3‐hexylthiophene) nanocomposites

Abstract

Conjugated polymer‐layered filler nanocomposites have received extensive interest as multifunctional materials in various futuristic applications. In this study, the effect of graphene oxide (GO) particle size on the synthesis, optical, and electrochemical properties of in situ prepared graphene oxide (GO)‐poly(3‐hexylthiophene) (P3HT) nanocomposites have been studied. The intercalation of GO with P3HT is inferred from shifting and broadening of the characteristic D‐ and G‐bands of GO in Raman spectra and also the vibrational frequencies in FTIR. This interaction is further confirmed from increase of the optical band gap and the ellipsometry data. The UV–visible absorption maximum (λmax) of P3HT decreases from 438 to 418 nm in the nanocomposite owing to ionic interactions between GO and the polymer causing a decrease of the polymer conjugation length. Compared to the homopolymer, the emission maximum of the composite is broadened and enhanced in intensity with 10 wt% GO but emission quenching is observed with GO nanoparticles. The evidence of polymer intercalation was also deduced from the determination of the basal spacing and unit cell dimensions of GO, using X‐ray diffraction data. Morphological studies using field emission scanning electron microscopy suggest that the crystalline rod‐like structures observed in the homopolymer have changed to more amorphous, flaky, and porous structures. The cyclic voltammetry studies show an increase in current with increasing GO content in the porous nanocomposites. POLYM. COMPOS., 38:852–862, 2017. © 2015 Society of Plastics Engineers

Effect of flake size on thermal properties of graphene oxide/poly(methyl methacrylate) composites prepared via in situ polymerization

“…So far, most studies have focused on the functionalization of GO to improve dispersion of GO and enhance interfacial strength during in situ polymerization process. However, it is worth noting that the characteristic nature of nanofillers also play an important role in determining the properties of composites . To our knowledge, no study has been conducted to study the relations between GO sheet size and thermal properties of polymer composites prepared via in situ polymerization up to now.…”

Lateral size reduction of graphene oxide preserving its electronic properties and chemical functionality

“…5 As the aforementioned oxidation degree is carefully taken into consideration in a lateral size reduction process, allows further ne tuning when GO is chemically reduced, i.e., rGO nal surface chemistry and characteristics through simple chemical techniques. 6,7 When both parameters are accurately controlled, is possible to use GO not only as graphene precursor, but also in different applications like biomedicine, 11,18,23,27 catalysis, 22 polymer nanocomposites, 28,29 adsorption, 24 electronics, 25 organic solar cells, 30,31 and specially in energy storage such as supercapacitors, where if the precise C/O ratio and size can be controlled, the small lateral size GO could be used in hierarchical structures. [32][33][34] Based on that, is crucial to control both parameters, because if a lateral size reduction leads into a C/O ratio modication on GO, it will affect the electronic properties, its solubility and further chemical functionalisation.…”

Studies of Reduced Graphene Oxide and Graphite Oxide in the Aspect of Their Possible Application in Gas Sensors

“…Based on research conducted all over the world, it can be stated that materials like ZnO [ 3 ], TiO 2 [ 4 ] and WO 3 [ 5 ] can serve as excellent sensing layers. Also hybrid materials of conductive polymers with two-dimensional nanofilters ought to be taken into account (e.g., graphene oxide-poly (3-hexylthiophene) nanocomposites) [ 6 ]. It is to be stressed that the use of carbon materials just for decorating for instance with palladium [ 7 , 8 ] or for use in hybrids (and also in pristine form) are becoming more and more interesting, not only in the sensor domain The range of potential applications of carbon structures is rather wide and information provided in the respective literature indicates that carbon nanomaterials may be potentially used, among others, as selective molecular membranes [ 9 ].…”