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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]

Edge‐NFx (x=1 or 2) protected graphitic nanoplatelets (NFGnPs) are synthesized for the first time as a stable anode material for lithium storage. The NFGnPs are prepared via mechanochemical reaction, by ball‐milling graphite in the presence of nitrogen trifluoride (NF3) gas. The average grain size of the NFGnPs is dramatically reduced compared to the starting graphite. The ball‐milling effectively unzips graphitic C−C bonds, generating active carbon species (C.), which form edge C−NFx bonds and delaminate the graphite layers into a few layered NFGnPs. The resulting NFGnPs have a large specific surface area (671.0 m2 g−1). The edge functionalities of the NFGnPs consist of major C(C)=NF1 and minor C−NF2 moieties. Because of their large specific surface area, the NFGnPs display high average reversible capacities of 850.5, 722.4, 576.4, 482.0, 369.1, 229.7, 127.5 mAh g−1 at 0.2, 0.5, 1, 2, 5 and 10 C, respectively, with excellent rate capability. More importantly, due to the edge protection provided by the stable C(C)=NF1 bonds (pseudo‐aromatic), the NFGnPs maintain a high reversible charge capacity of 421.6 mAh g−1 at 2 C, with an initial capacity retention of 78.3 % after 200 cycles. [ABSTRACT FROM AUTHOR]

Nonmetallic carbon‐based nanomaterials (CNMs) are important in various potential applications, especially after the emergence of graphene and carbon nanotubes, which demonstrate outstanding properties arising from their unique nanostructures. The pristine graphitic structure of CNMs consists of sp2 hybrid C−C bonds and is considered to be neutral in nature with low wettability and poor reactivity. To improve its compatibility with other materials and, hence, for greater applicability, CNMs are generally required to be functionalized effectively and/or doped with heteroatoms in their graphitic frameworks for feasible interfacial interactions. Among the various possible functional/doping elements, nitrogen (N) atoms have received much attention given their potential to fine tune the intrinsic properties, such as the work‐function, charge carrier concentration, surface energy, and polarization, of CNMs. N‐doping improves the surface energy and reactivity with enhanced charge polarization and minimal damage to carbon frameworks. The modified surface energy and chemical activity of N‐doped carbon nanomaterials (NCNMs) can be useful for a broad range of applications, including fuel cells, solar cells, Li‐ion batteries, supercapacitors, chemical catalysts, catalyst supports, and so forth. [ABSTRACT FROM AUTHOR]