EELS analysis of Nylon 6 nanofibers reinforced with nitroxide-functionalized graphene oxide

Abstract

A detailed analysis by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) of nitroxide-functionalized graphene oxide layers (GOFT) dispersed in Nylon 6 nanofibers is reported herein. The functionalization and exfoliation process of graphite oxide to GOFT was confirmed by TEM using electron diffraction patterns (EDP), wherein 1 to 4 graphene layers of GOFT were observed. The distribution and alignment of GOFT layers within a sample of Nylon 6 nanofiber reveals that GOFT platelets are mainly within the fiber, but some were partially protruding from it. Furthermore, Nylon 6 nanofibers exhibit an average diameter of 225 nm with several microns in length. GOFT platelets embedded into the fiber, the pristine fiber, and amorphous carbon were analyzed by EELS where each spectra [corresponding to the carbon edge (C-K)] exhibited changes in the fine structure, allowing a clear distinction between: i) GOFT single-layers, ii) Nylon-6 nanofibers, and iii) the carbon substrate. EELS analysis is presented here for the first time as a powerful tool to identify functionalized graphene single-layers (< 4 layers of GOFT) into a Nylon 6 nanofiber composite.

Bamboo‐Like Nitrogen‐Doped Carbon Nanotube Forests as Durable Metal‐Free Catalysts for Self‐Powered Flexible Li–CO2 Batteries

“…When discharged, the peak intensity of N‐6 and N‐Q is found to clearly decrease to some extent, which may be caused by coverage of N‐6 and partial N‐Q active sites by Li 2 CO 3 product and detecting hardly by the surface‐sensitive XPS. When recharged, all of these peaks reappeared (Figure n) …”

The Role of α, γ, and Metastable Polymorphs on Electrospun Polyamide 6/Functionalized Graphene Oxide

“…[ 30 ] A proposed functionalization mechanism of GO with oxoammonium salts (Br‐TEMPO) to produce nitroxide‐functionalized graphene oxide (GOFT) has been reported by our work group before (Figure S1, Supporting Information). [ 28,31 ]…”

Carbon Nanotube and Graphene Based Polyamide Electrospun Nanocomposites: A Review

“…Electrospinning provides electrostatic stretching forces (whipping elongation) for overcoming any entanglement of nanomaterials [70]. A uniform distribution of carbon nanomaterials is critical for preventing nanofiller protrusion, notches, and beads across the fibre body [56,70]. Polymer solution properties, such as molecular weight, solution viscosity, surface tension, solution conductivity, and dielectric constant, are critical factors that affect the electrospun fibre morphology [68,83,84].…”

“…This behaviour is due to the converging nanoscale jet reducing the number of available orientations in the flow field [53]. NGO was aligned within the PA6 nanofibres meanwhile agglomerates of the nanofiller could hardly be aligned; therefore the NGO sheets protruded from the fibres; Figure 7 shows the NGO/PA6 nanofibres [56]. Zomer Volpato et al found that the surface of PA6 electrospun fibres was rough with defects attributed to the fibre stretching and the presence of O-MWCNTs in the nanocomposite fibres resulted in greater surface roughness compared to the control nanofibres [53].…”