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Recent clinical outbreaks of infectious diseases caused by pathogenic microorganisms, such as viruses, bacteria, and fungi, along with the emergence of unwanted microorganisms in industrial settings, have significantly reduced efficiency. Graphene has recently attracted significant attention as a potential antimicrobial agent because of its low toxicity, ease of production and functionalization, and high solubility in water. The presence of oxygen functional groups allows the interaction of the compound with bacteria and other biomolecules, making it an interesting candidate for antimicrobial therapy. Moreover, integrating graphene into copper coatings has been shown to enhance their antimicrobial properties. However, the implementation of copper–graphene composite coatings is currently limited by the difficulty of uniformly distributing graphene within the copper matrix. Copper (Cu)-doped graphitic nanoplatelets (CuGnPs), one option to overcome this challenge, are made via a mechanochemical reaction between solid graphite and Cu powder. The configuration of C–Cu bonds within CuGnPs can be identified using a range of analytical techniques, including transmission electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and time-of-flight secondary ion mass spectrometry. To evaluate the antibacterial activity of the Cu-GnPs, we employed Escherichia coli or Staphylococcus aureus. Various amounts (250, 500, 750, and 1000 μg/mL) of prepared CuGnP samples were incubated in a bacterial suspension for 3 or 6 h at 150 rpm and 37 °C for a colony-forming unit assay. Three hours and six hours of treatment of the bacteria with CuGnPs led to a significant difference in bacterial survival compared with that of the control. It was observed that CuGnPs, with copper bound to graphene oxide, more effectively inhibited the proliferation of E. coli compared with nanoplatelets containing graphene oxide alone. These findings suggest that the unique properties of CuGnPs, such as C–Cu bonds, high surface area, and the coexistence of micropores and mesopores, are valuable for exerting strong antimicrobial effects making CuGnPs effective at preventing bacterial colonization on industrial surfaces. [ABSTRACT FROM AUTHOR]

Cyano-functionalized graphitic nanoplatelets (CyGNs) are synthesized by means of a mechanochemical reaction between graphite and acrylonitrile. The resulting CyGNs exhibit excellent mechanical properties and are highly dispersible in various solvents (i.e., THF). Due to their chemical compatibility (specifically, cyano functional groups), the CyGNs serve effectively as a reinforcing filler for acrylonitrile butadiene styrene (ABS) resin. Consequently, compared to pure ABS, CyGN&ABS-X demonstrates improved mechanical properties and better thermal stability. Notably, the CyGN&ABS-1 specimen exhibits significant enhancements in the tensile strength (26 ± 1 MPa), Young's modulus (992 ± 71 MPa), and tensile toughness (22 ± 3 MPa), representing increases of approximately 130.6%, 19.2%, and 59.6%, respectively, over pure ABS. This underscores the ability of a mechanochemical reaction to directly modify the functional groups of graphitic nanoplatelets (GnPs) as fillers, facilitating their strong compatibility with a variety of polymers, including copolymers. [ABSTRACT FROM AUTHOR]

Heptene‐graphitic nanoplatelets (HtGNP) serve as a filler for high density polyethylene (HDPE), generated through a mechanochemical reaction involving graphite and 1‐heptene. Various analyses indicate the efficient exfoliation of graphite into HtGNP, characterized by exceptional traits. Consequently, HtGNP & HDPE_5 nanocomposites, produced via the solution process, exhibit significantly increased tensile strength and Young's modulus, boasting corresponding increases of 27.7% and 13.7% compared to pure HDPE. Thus, owing to their outstanding performance, HtGNP emerges as a promising option in the form of a novel reinforcing additive for various hydrocarbon polymers. [ABSTRACT FROM AUTHOR]

Graphitic nanoplatelets (GnPs), edge‐selectively carboxylated graphitic nanoplatelets (ECGnPs), are functionalized with a carboxylic acid at the edge increasing their surface area, and are highly dispersible in various solvents. However, there is a limit in that the basal plane remains intact because it is functionalized only in the part where the radical is generated at the edge. Here, we activate ECGnPs to have porous structures by flowing CO2 at 900 °C. Etching of the ECGnPs structure was performed through the Boudouard reaction, and the surface area increased from 579 m2 g−1 to a maximum of 2462 m2 g−1. In addition, the pore structure was investigated with various adsorption gases (CH4, Ar, CO2, H2, and N2) according to the reaction time. This study provides the overall green chemistry in that it utilizes CO2 from manufacturing to activation compared to the process of activating with conventional chemical treatment. [ABSTRACT FROM AUTHOR]

Energy storage systems (ESSs) are attracting increasing attention for the development of sustainable and renewable energy technologies owing to limited fossil fuels. Supercapacitors are gaining significant interest as energy storage devices owing to their high-power density and long-term cycle stability. The use of suitable electrode materials affects the performance of supercapacitors. In this study, we fabricated a carboxyl-doped graphene nanoplatelet (CGnP) via a mechanochemical reaction. Additionally, CGnP was activated by controlling parameters such as temperature, flow rate, and maintenance period and evaluated as an electrode material for supercapacitors. The effect of the specific surface area (SSA) and functional groups of the fabricated samples on the capacitance was confirmed by controlling the activation parameters. The activated CGnP with 300 mL/min of CO2 at 1173 K for 4 h exhibited a high SSA of 1300 m2/g. The activated CGnP (180 F/g), with a high SSA, showed an increased capacitance of 46% compared to pristine CGnP (123 F/g). Additionally, activated CGnP1100 demonstrated good wettability and exhibited excellent stability with a low capacitance decrease of 6.1%, even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Hexene‐doping graphitic nanoplatelets (HxGNs), as a new filler, have extraordinary properties (e.g., hexene‐functionalization, wedge‐shaped pore, high specific surface areas, and so on), and interfacial interactions with hydrophobic polymers. Thus, the HxGNs sufficiently increase the mechanical properties of poly(vinyl chloride) (PVC). HxGN@PVC_X nanocomposites can be prepared easily with a solution casting method because the HxGNs are well dispersed in tetrahydrofuran. The tensile strength, Young's modulus, toughness, and strain‐to‐failure of HxGN@PVC_5 nanocomposites increase by approximately 33.1%, 27.3%, 58.6%, and 40.5%, respectively, compared with pure PVC. Especially, the low toughness of PVC, which hinders practical applications, has been greatly improved. The improved performance is from the outstanding properties of the HxGNs and the excellent interfacial interactions between the HxGNs and PVC chain. As a result, HxGNs as a filler act as a reinforcing agent and plasticizer for the PVC matrix. Highlights: The performance of the HxGN@PVC_5 nanocomposites is increased.The HxGN into PVC matrix is effective to overcome the disadvantages of PVC.A mechanochemical reaction can make graphitic nanoplatelets with specific groups.Graphitic nanoplatelets with specific groups can be used as new filler. [ABSTRACT FROM AUTHOR]

Hexene-functionalized graphitic nanoplatelets (He- f -GN) were easily prepared using a mechanochemical reaction between solid graphite and liquid 1-hexene. The He- f -GN exhibited outstanding properties (e.g., high specific surface area, high crystallinity and so on) and could be well distributed in various solvents including formic acid. The He- f -GN/Nylon 6_X nanocomposites were simply prepared using the solution method, and showed excellent mechanical properties and thermal stability compared with the neat Nylon 6. Specifically, the tensile strength and Young's modulus of the He- f -GN/Nylon 6_1 nanocomposites increased by approximately 32.5% and 33.7%, respectively, compared to the neat Nylon 6 due to the special properties of the He- f -GN and its excellent compatibility with Nylon 6 chains. The He- f -GN also acts as nucleation sites, increasing the crystallinity of Nylon 6, and generated hydrogen bonds with the amide groups of the Nylon 6. The new filler, He- f -GN, provides an effective way to increase the performance of polymer, demonstrating good application prospects. [ABSTRACT FROM AUTHOR]

Abstract The feasibility of edge-functionalization of graphite was tested via the model reaction between pyrene and 4-(2,4,6-trimethylphenyloxy)benzamide (TMPBA) in poly(phosphoric acid) (PPA)/phosphorous pentoxide (P2O5) medium. The functionalization was confirmed by various characterization techniques. On the basis of the model study, the reaction condition could be extended to the edge-functionalization of graphite with TMPBA. Preliminary results showed that the resultant TMPBA-grafted graphite (graphite-g-TMPBA) was found to be readily dispersible in N-methyl-2-pyrrolidone (NMP) and can be used as a precursor for edge-functionalized graphene (EFG).