Mechanical Properties of Green Synthesized Graphene Nano-Composite Samples

Abstract

Graphene quantum dots are zero-dimensional nanoparticles that are used widely in advanced composite materials such as filtration membranes, adsorbent materials, optical devices, biomedical applications (especially biosensors), flame retardancy, and automotive, aerospace, agricultural and environmental applications. In this article, the mechanical properties (flexural strength, flexural strain and elastic modulus) of polymer-based nanocomposites will be investigated. The main novelty of the current work is the green synthesis of graphene quantum dots which were extracted from lemon juice. XRD and FTIR tests have been conducted to determine the composition of the prepared powder. The polyester resin and graphene quantum dots were mixed with different weight percentages (0.25%, 0.5% and 1% wt. graphene) and processed to fabricate nanocomposite samples. The mechanical properties of the prepared samples were measured according to the ASTM D790-17 standard testing method. The experimental results show that the strength increased from 80 MPa to about 112 MPa (40% increase in strength) by adding 0.25% wt. graphene quantum dots. The flexural modulus decreased from 2.70 GPa to 2.06 GPa by adding 1% wt. graphene content (23% decrease). The flexural strain increased considerably (up to 14.2%) by adding 1% wt. graphene quantum dots. Consequently, the ductility of the nanocomposites increased by adding green synthesized graphene quantum dots. The fracture behavior changed from brittle fracture mode to ductile fracture mode by adding the graphene quantum dots. Additionally, a flame retardancy test has been carried out by implementing the UL-94 test. The fabricated nanocomposites showed fire retardancy due to char barrier formation on the surface of the nanocomposites.

Ag-NP-Decorated Carbon Nanostructures: Synthesis, Characterization, and Antimicrobial Properties

“…The XRD pattern for GNPs reveals only the crystal reflection of graphitic carbon at 2θ = 26.44° (Figure ), in accordance with file JCPDS card no. 08-0415. , Figure also unveils the hexagonal close-packed (hcp) (002) crystal reflection of pristine rGO at 2θ = 26.20°. This broad and slightly curved peak contrasts with the narrow peak observed for GNPs.…”

“…08-0415. 44,45 Figure 4 also unveils the hexagonal close-packed (hcp) (002) crystal reflection of pristine rGO at 2θ = 26.20°. This broad and slightly curved peak contrasts with the narrow peak observed for GNPs.…”

Experimental investigation on the mechanical properties of Al2024 doped with green synthesized quantum dots

“…Additionally, numerous micromechanical systems for calculating the Aluminum matrix composites strength [28] with the help of various strengthening methods are explained. More significantly, depending on the observed features, promising and potential applications of Aluminum matrix composites have been suggested for a variety of industrial sectors, including the automotive, space, aerospace, electrical, energy, and electronics systems sectors.…”

Green fluorescent unsaturated polyester/graphitic carbon nitride quantum dots nanocomposites: Preparation and study of UV-resistance, mechanical and viscoelastic properties

“…Fractures deflection, particles separation and development of empty spaces in polymer are regarded three major mechanisms leading to fracture and breaking apart in the polymer nanocomposites. 51 In the presence of CNQDs, the fractures direction changes and coalescence of microcavities is delayed. According to this, the maximal and minimal tensile strength are respectively offered by UP/ CNQDs 0.75 wt% and UP films.…”