Graphene/Carbon Dot Hybrid Thin Films Prepared by a Modified Langmuir–Schaefer Method

Abstract

The special electronic, optical, thermal, and mechanical properties of graphene resulting from its 2D nature, as well as the ease of functionalizing it through a simple acid treatment, make graphene an ideal building block for the development of new hybrid nanostructures with well-defined dimensions and behavior. Such hybrids have great potential as active materials in applications such as gas storage, gas/liquid separation, photocatalysis, bioimaging, optoelectronics, and nanosensing. In this study, luminescent carbon dots (C-dots) were sandwiched between oxidized graphene sheets to form novel hybrid multilayer films. Our thin-film preparation approach combines self-assembly with the Langmuir–Schaefer deposition and uses graphene oxide nanosheets as template for grafting C-dots in a bidimensional array. Repeating the cycle results in a facile and low-cost layer-by-layer procedure for the formation of highly ordered hybrid multilayers, which were characterized by photoluminescence, UV–visible, X-ray photoelectron, and Raman spectroscopies, as well as X-ray diffraction and atomic force microscopy.

Controlled deposition of fullerene derivatives within a graphene template by means of a modified Langmuir-Schaefer method

“…These novel fullerene-based hybrid films are excellent candidate nanomaterials for potential application where graphene is already been studied such us gas/liquid separation [57], sensors [55,58], photovoltaics [86] or electronic devices [54]. Moreover, the different surface properties of the hybrid films are crucial for a plethora of bio-applications since the adsorption or the adhesion of cells or enzymes depends on the surface energy related to the wetting nature of the surface [87,88].…”

“…This pressure was maintained throughout the deposition process. The hybrid Langmuir layers (ODA-GO) were transferred onto the Si-wafer substrates by horizontal dipping (Langmuir Schaefer technique), with downward and lifting speeds of 10 and 5 mm min À1 , respectively [47,57]. After the horizontal lift of a substrate, the ODA-GO film was dipped into an aqueous solution of fullerols (0.2 mg mL À1 ).…”

“…3 tions from two dimensional gas to condensed liquid and then to solid during the compression process. The fact that the compression of ODA on top of the GO suspension gives rise to an increase the surface pressure much earlier during the compression compared to that for ODA spread on pure water, indicates that a hybrid floating layer of functionalised ODA-GO has been formed [47,57], that is related to the hybridization of GO nanosheets by covalent bonding via the amide functionality of ODA [67]. Representative AFM images of hybrid Langmuir monolayers (ODA-GO) transferred onto the Si-wafer at different surface pressures in the LB trough, namely 5, 10, 15 and 20 mN/m, are shown in Fig.…”

Facile MoS2 Growth on Reduced Graphene-Oxide via Liquid Phase Method

“…The third peak at 286.2 eV (9.0%) originates from the C-O-C epoxide/ether groups, whereas carbonyl functional groups (C=O) are associated with the peak at 287.3 eV (3.5%). Finally, the higher binding energy contribution recorded at 288.8 eV (1.7%) corresponds to the carboxyl groups (O-C=O) (Dimos et al, 2017;Kouloumpis et al, 2017;Tzitzios et al, 2017).…”

Green synthetic route of carbon quantum dot‐reinforced graphene oxide‐poly(vinylidene fluoride‐co‐hexa fluoropropylene) nanocomposites: Toward high dielectric constant and suppressed loss

“…In Figure (a,b), it is observed that Raman spectra of both GO and CQD exhibits two peaks, at G band (1592 and 1582 cm −1 ) and D band (1347 and 1352 cm −1 ) of sp 3 and sp 2 hybridized carbon atoms, respectively. It reveals that the G‐band of GO is shifting toward higher frequencies (blue shift), this transition may refer to graphite amorphization and identical with the mechanically exfoliated graphene …”