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Due to enormous applications of large-area graphene with high quality, the epitaxial growth strategies have drawn a plethora of attention. However, the bottleneck in the production of graphene has caused delayed development in recent years, which is owing to the poor understanding of interaction mechanisms between graphene and the underlying metallic and non-metallic substrate. To understand the thermodynamics of graphene–substrate interface and growth kinetics, accurate density functional theory (DFT) calculations have been proved as an effective way, in terms of cost and time, compared with traditional experimental methods, which can calculate the interaction between graphene and substrates, helping us to better understand the practical phenomena. Here, we show the use of DFT methods to evaluate both van der Waals interaction and covalent bonding. Many of computational results fit well with the experimental observations. To address the relative low accuracy and small computation capacity (number of atoms) of common DFT models, we suggest that the machine learning (ML) methods will be a fresh impetus for epitaxial growth strategy of graphene, which put forward effective interpretations for complicated interconnections and correlations among the properties, thereby enabling ML a promising strategy for understanding, design, and synthesis of graphene over other 2D materials. [ABSTRACT FROM AUTHOR]

Tunability of interfacial effects between two-dimensional (2D) crystals is crucial not only for understanding the intrinsic properties of each system, but also for designing electronic devices based on ultra-thin heterostructures. A prerequisite of such heterostructure engineering is the availability of 2D crystals with different degrees of interfacial interactions. In this work, we report a controlled epitaxial growth of monolayer TaSe2 with different structural phases, 1H and 1 T, on a bilayer graphene (BLG) substrate using molecular beam epitaxy, and its impact on the electronic properties of the heterostructures using angle-resolved photoemission spectroscopy. 1H-TaSe2 exhibits significant charge transfer and band hybridization at the interface, whereas 1 T-TaSe2 shows weak interactions with the substrate. The distinct interfacial interactions are attributed to the dual effects from the differences of the work functions as well as the relative interlayer distance between TaSe2 films and BLG substrate. The method demonstrated here provides a viable route towards interface engineering in a variety of transition-metal dichalcogenides that can be applied to future nano-devices with designed electronic properties.

A perfect absorber in the terahertz band with ultra-broadband and triple narrowband is achieved, using Vanadium Dioxide (VO2) and patterned graphene hybrid metamaterials, which can be converted by adjusting the temperature. When only VO2 is present in the structure, the absorption spectrum shows broadband absorption in metallic phases of VO2. Adding graphene to metallic VO2, the absorption bandwidth over 95% is expanded to 5.5 THz, which is 1.9 times broader compared to the absence of graphene, and the absorption bandwidth over 99% increases to 1.72 THz. Adding graphene to insulating VO2, three narrowband absorptions appear with absorption rates approaching 100%. Polarization characteristics show that ultra-broadband is insensitive to polarization angle, while multi-frequency narrowband exhibits sensitivity. Therefore, the proposed tunable multifunctional absorber can greatly optimize the absorption capacity of ultra-broadband and multi-frequency narrow bands, demonstrating great potential in future practical applications. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have rapidly emerged as a new family of carbon‐based nanomaterials since their initial discovery two decades ago. Numerous appealing properties, such as precursor and synthesis process flexibility, tunable photoluminescence, and good biocompatibility, have enabled their widespread applications in sensing, catalysis, energy, and biomedical fields. As the field expands, notable efforts have recently focused on mechanistically elucidating the structural formation and optical behavior of CDs. However, the absence of "clean" CDs presents a major obstacle to achieving a solid understanding of these aspects. Often, the claimed CDs are, in fact, a mixture of small molecules, oligomers, nano‐sized aggregates, or even microparticles. Such coexistence of impurities markedly impacts the physicochemical properties of resulting CD‐based mixtures, hampering the resolution of key mechanistic questions. Here, we aim to address this fundamental shortcoming of the field, going beyond the customary focus of the existing reviews that predominantly cover synthesis, optical performance, and application prospects. We begin with an overview of CD synthesis and then thoroughly examine the purification methods, including filtration, dialysis, electrophoresis, and chromatography. The insights provided here will guide the researchers towards obtaining high‐quality CDs, employing proper combinations of available tools, and ultimately paving the way for more demanding applications. [ABSTRACT FROM AUTHOR]

Hydrogen holds the promise of replacing fossil fuels and offers a sustainable pathway for energy generation. However, the large-scale production of hydrogen via the environment friendly electrocatalytic process relies heavily on the performance of electrocatalysts. In this study, we investigate the electrocatalytic performance of graphene nanosheets (GNS), molybdenum disulfide (MoS 2), ruthenium dioxide (RuO 2), and their composites for hydrogen evolution reaction (HER), a novel combination that has not been explored in previous literature. We synthesize the materials using Liquid Phase Exfoliation at 500 and 1000 RPMs for GNS and MoS 2 and via hydrothermal methods for RuO 2 nanosheets and nanoparticles, aiming to exploit synergistic effects for enhanced activity and stability. The synthesized GNS-1000/MoS 2 -1000/RuO 2 -NSs composite demonstrates promising HER results, showcasing a low overpotential of 63 mV and a reduced Tafel slope of 59 mV/dec. This improvement indicates enhanced electron transfer, improved active site dispersion, and increased surface area due to the synergistic effects, which also aids in long-term electrochemical stability. Our study underlines the potential of GNS/MoS 2 /RuO 2 composites, particularly the GNS-1000/MoS 2 -1000/RuO 2 -NSs, in transforming hydrogen production methods and promoting efficient, sustainable energy solutions. The implications of our findings extend the boundaries of materials engineering, edging us closer to a sustainable energy future. • Novel GNS/MoS 2 /RuO 2 catalyst enhances HER with low overpotential and Tafel slope. • Synergistic effects of GNS, MoS 2 , and RuO 2 boost electron transfer in HER. • Cost-effective alternative to platinum catalysts developed for hydrogen production. • Optimized synthesis improves catalytic activity and stability in HER. • Composite catalyst offers potential for sustainable energy applications. [ABSTRACT FROM AUTHOR]

The commercialization process of the direct methanol fuel cell technology is seriously blocked by the insufficient catalytic efficiency and low natural abundance of traditional Pt-based anode catalysts, which motivates the research on the design and synthesis of advanced non-Pt catalysts with high performance and acceptable costs. Herein, we report a controllable and robust building method to the bottom-up preparation of ultrasmall Rh-decorated porous heterostructures stereoassembled from Ti 3 C 2 T x MXene and reduced graphene oxide nanosheets (Rh/MX-RGO) through a facile solvothermal process. The presence of three-dimensional crosslinked graphene aerogel network provides abundant porosity and inhibits the nanosheets from longitudinal restacking, while the introduction of MXene offers extra anchoring sites for the immobilization of Rh nanoparticles as well as ameliorates their electronic structure. Consequently, the resultant Rh/MX-RGO catalyst manifests impressive alkaline methanol oxidation properties, including a large electrochemically active surface area of 91.8 m2 g−1, a high mass (specific) activity of 1605.0 mA mg−1 (1.74 mA cm−2), a small Tafel slope of 89 mV decade−1, strong poison resistance, and reliable long-term stability, all of which significantly outperform those of reference Rh/MXene, Rh/RGO, Rh/carbon nanotube, Rh/carbon black, and widely-used Pt/carbon black and Pd/carbon black catalysts. A controllable and robust building method is developed to the bottom-up synthesis of ultrasmall Rh-decorated porous heterostructures stereoassembled from Ti 3 C 2 T x MXene and graphene, which demonstrate superior electrocatalytic performance toward methanol electrooxidation. [Display omitted] • The bottom-up construction of porous heterostructures stereoassembled from MXene and graphene is achieved. • Well-dispersive Rh nanocrystals are in situ immobilized on crosslinked MXene-graphene frameworks. • The unique architectural design prevents the nanosheet restacking and ameliorates the Rh electronic structure. • The resulting heterostructure expresses excellent catalytic properties toward methanol electrooxidation. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a compact triple‐band frequency‐tunable (FT) hexagonal‐shaped graphene antenna through a machine learning (ML) approach for terahertz (THz) application is presented. The proposed THz antenna is designed on a polyamide (∈r=3.5$$ {\in}_r=3.5 $$) substrate with a thickness of 10 μm, and graphene is used as an antenna radiator. The size of the substrate is 38 × 46 μm2. The FT is achieved by changing the chemical potential of graphene material. The performance of the proposed THz antenna has been investigated, and the impacts of several conducting materials like gold, aluminum, copper, and graphene and dielectric materials like Rogers RT/duroid 5880, polyamide, quartz, and SiO2 are explored. The proposed THz antenna provides three operating bands. The frequency of operation in Band‐1 is 2.51–5.05 THz, Band‐2 is 5.99–7.43 THz, and Band‐3 is 7.94–9.63 THz. The bandwidth in Band‐1, Band‐2, and Band‐3 are 2.54, 1.44, and 1.69 THz, respectively. The % of impedance bandwidth in Band‐1, Band‐2, and Band‐3 are 67.19%, 24.02%, and 21.28% respectively. The proposed antenna has a maximum peak gain of 5 dBi. The proposed antenna is optimized through various ML algorithms like random forest (RF), extreme gradient boosting (XGB), K‐nearest neighbor (KNN), decision tree (DT), and artificial neural network (ANN). The RF algorithm gives more than 99% accuracy compared to other ML algorithms and accurately predicts the S11 of the proposed antenna. The proposed THz antenna would be suitable for applications related to imaging, medical, sensing, and ultra‐speed short‐distance communication applications in the THz region. [ABSTRACT FROM AUTHOR]

Highlights Fiber‐reinforced polymer composites (FRPCs) have become integral to various industries due to their exceptional strength‐to‐weight ratio, corrosion resistance, and versatility. Recent advancements in the properties and recycling of FRPCs reflect significant progress in performance and sustainability. This paper reviews the latest developments in FRPC technology, highlighting innovations in material formulation, including advancements in fiber types, matrix materials, and hybrid composites that enhance mechanical properties. Furthermore, this review emphasizes the modification of matrices by incorporating graphene, which aims to improve the chemical bonding and mechanical interlocking between fiber and matrix. Additionally, it addresses recent breakthroughs in recycling technologies, focusing on methods such as chemical recycling, mechanical recycling, and developing eco‐friendly matrices. Integrating these advancements aims to improve the lifecycle management of FRPCs, reduce environmental impact, and support the transition towards a circular economy. This review underscores the balance between enhancing composite performance and promoting sustainable practices, paving the way for more environmentally responsible applications of FRPCs. The different types of fiber‐reinforced polymer composites have been thoroughly reviewed. How does graphene affect the mechanical behavior of fiber composite laminates? Provide a systematic correlation and comparison between fabrication methods, materials, and properties. The recycling methods for fiber‐reinforced polymer composites have been deliberated. [ABSTRACT FROM AUTHOR]

In the present work, a thermographic procedure to evaluate in-plane thermal diffusivity and parallel finite element method were applied to a metal matrix composite layer. The observed coatings were realized with copper and graphene. Graphene application is more interesting in various fields, but this innovative technology shows various issues of application like the cluster formation that reduces mechanical and physic properties of coating. In this work, the application of graphene can be made with electrodeposition, and a matrix of copper was obtained with subsequent electrodeposition processes. This innovative methodology allows to avoid the issue of cluster formation and increases the amount of graphene in the final layer. In addition, the implementation of multi-coating increases thermal diffusivity by up to 65% obtaining results difficult to reach with a single layer of graphene. In addition, a FEA simulation was carried out to observe the compliance of the numerical method aimed at predicting the thermal properties of the obtained composite. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Graphene nanoribbons (GNRs), which can be considered as a special type of conjugated polymers, are quasi‐one‐dimensional graphene cutouts with an opened band gap, revealing great potential as functional materials in optoelectronic, spintronic, and energy‐related applications. An effective strategy to modulate the properties of GNRs is doping heteroatoms into the π‐skeleton. Thanks to the bottom‐up synthetic approach, a number of heteroatom‐doped GNRs with precise structures have been reported, exhibiting intriguing properties. Nevertheless, a comprehensive summary of the progress of this field has remained elusive. In this review, we summarize the history and advances in bottom‐up synthesized heteroatom‐doped GNRs, including their synthetic routes, electronic properties, and promising applications. We hope to establish the reliable structure–property relationship, and provide guidance for the molecular design of heteroatom‐doped GNRs in the future. [ABSTRACT FROM AUTHOR]

This work examines the effects of varying weight percentages (0.1, 0.3, and 0.5 wt%) of pristine and functionalized graphene (–COOH, –OH, and –NH2) on the compression and impact strength of carbon fiber-reinforced polymer (CFRP) composite laminates. The laminates were fabricated in two different stacking sequences of carbon fiber in composite laminates, i.e., 0/90° and 0/90/ ± 45° by hand layup technique. Experimental results showed that the inclusion of graphene in epoxy matrix enhances the compressive strength and impact characteristics, namely impact force, displacement, energy profile, and damage behavior of CFRP laminates. Moreover, the orientation of carbon fiber layers in laminates affects the internal damage behavior of specimens and the delamination between fiber layers. The maximum improvements of 38.65 and 76.82% are noticed in the compressive strengths of 0/90° and 0/90/ ± 45° stacked laminates with the reinforcement of 0.1 wt% of pristine and 0.3 wt% of –COOH functionalized graphene to epoxy, respectively. In summary, the test results have shown that using graphene as a reinforcing filler can significantly improve the impact performance of CFRP composites. [ABSTRACT FROM AUTHOR]

Conductive coatings provide electromagnetic shielding against interference and radiation from electromagnetic waves. This is critical for electronic devices, communications equipment, medical instruments, and other industries. In this paper, XRD and Raman proved that Al3+ doped anatase, rutile, and brookite coexisting mixed crystalline phase TiO 2 , which evolved into highly conductive powder materials after ultrasonically compounding graphene, are prepared by simply controlling the calcination temperature. Tauc spectra proved the three-phase heterojunction shortens the distance between the conduction and valence bands, and electron jumping becomes easy. XPS proves that with low-price Al3+, the high-price Ti4+ in the lattice will be replaced, forming oxygen vacancies. A fast charge transfer pathway (Al–O–C) is established between Al3+ and graphene, and the synergistic effect of the two greatly reduces the resistivity. Four-probe test material resistance learned the resistivity of TAl-G is 57 % lower than that of T-G. At the same time, the excellent electrical conductivity of the TAl-G composite makes it suitable for practical applications in antistatic coatings, while the significantly shorter bandgap gives it great potential for photoelectrocatalysis. [ABSTRACT FROM AUTHOR]

This paper investigates the wave propagation in the graphene platelets (GPLs)-enhanced functionally graded porous plates. The governing equations of motion are obtained using the first-order shear deformation plate theory (FSDT). Subsequently, the equations are transformed into the state-space form. The wave dispersion relation is derived by solving the state space equation by means of the method of reverberation-ray matrix and the accuracy of this approach is validated through a comparative analysis with the results from relevant literature. In addition, parametric analyses are carried out, including boundary conditions, porosity coefficient, GPL mass fraction, porosity distribution, GPL distribution, and thickness-to-width ratio, on the dispersion behavior of functionally graded GPLs-reinforced porous plates. The use of GPLs in these composites is particularly promising, and the findings offer valuable insights into the design of composites with tailored properties for specific engineering applications. [ABSTRACT FROM AUTHOR]

Cardiovascular disease such as myocardial infarction is one of the chief reasons for death universally. An extensive variety of natural and synthetic biodegradable polymers have been studied lately for cardiac tissue engineering applications. Cardiac tissue regeneration is a substitute approach for in situ cellular cardiomyoplasties, which is considered to renovate infarcted myocardium utilizing cells, scaffold, and growth factors. Polymer-based scaffolds including graphene and carbon nanotubes can be employed for heart tissue engineering. In this review, we consider the literature in terms of cardiac tissue engineering and discuss the most recent developments in terms of scaffold-based polymers for cardiac tissue regeneration. [ABSTRACT FROM AUTHOR]

Recently, hexagonal boron nitride (h‐BN) nanomaterials, e.g., nanosheets and nanotubes, have been predicted to be effective materials for reversible gas adsorption with high selectivity once charged. However, despite the encouraging theoretical predictions, sensing with h‐BN is difficult to realize experimentally due to its electrically insulating nature stemming from its large band gap. In this research, the controlled synthesis of high surface area hybrid h‐BN/graphene aerogel is reported, using high‐quality graphene as a template, and its application for selective gas sensing. It is discovered for the first time in this system that the difficulty of conversion in template synthesis of h‐BN is positively correlated with the quality of the carbon template, an observation that is verified on both graphene nanosheets and carbon nanotubes. The application of this hybrid material for gas sensing yields ppb level of detection limit and high selectivity for NH3. Through density functional theory calculations, the adsorption energy and charge transfer between NH3 molecules and aerogel are greatly enhanced. Therefore, this innovative approach promises new possibilities for the application of h‐BN in gas sensing, with the potential to play a significant role in gas capture, environmental monitoring, and other related fields. [ABSTRACT FROM AUTHOR]

Highlights Blends of natural rubber (NR)/chlorobutyl rubber (CIIR) (50/50), along with their nanocomposites containing varying amounts of graphene nanoparticles (GNPs) with and without silane, were prepared using different feeding sequences and mixers. The results indicated that when GNP was first mixed with NR before adding CIIR, the highest GNP content was found in NR; the oxygen permeability and diffusion coefficient decreased significantly by 37% and 55%, respectively. Conversely, when graphene was initially added to CIIR, it was distributed in both rubbers and at the interface, enhancing phase interaction and achieving a finer morphology. This sample exhibited the greatest improvement in mechanical properties due to specific localization of GNP and increased crosslink density. Using an internal mixer instead of a two‐roll mill improved graphene dispersion, reduced curing time, and enhanced mechanical properties. Although the presence of silane reduced graphene dispersion, it improved mechanical and barrier properties due to increased crosslink density. Oxygen permeability was reduced by up to 36% at 3 phr of GNP content with silane. This research proves that the mixing order and the type of mixing equipment are crucial in determining the final performance of rubber composites, as they significantly influence the dispersion and localization of fillers. NR/CIIR/GNP nanocomposites were prepared by different methods and evaluated. Adding NR/GNP to CIIR led to more presence of GNP in NR and lower permeability. By adding CIIR/GNP to NR, GNP were placed more at interface, modulus improved. Mixing in an internal mixer improved GNP dispersion compared to a two‐roll mill. Silane improved mechanical and barrier properties of NR/CIIR/GNP nanocomposite. [ABSTRACT FROM AUTHOR]

2D carbon allotropes with moderated electronic bandgaps are highly desirable for next‐generation carbon‐based nanoelectronics beyond graphene. Herein, the structural and electronic properties of bilayer α‐graphyne have been systematically investigated by using first‐principles calculations. Consequently, in addition to typical van der Waals (vdW) stacks of single‐layer α‐graphyne, new 2D carbon allotropes with purely sp2 or sp3 hybridizations can be achieved, arising from the absence of intralayer acetylene linkages during structural relaxation. Compared to the Dirac semimetallic behavior of monolayer α‐graphyne, the electronic structure of vdW bilayer α‐graphyne can be further modulated by stacking patterns, yet retains metallic characteristics. In contrast, intrinsic semiconducting characteristics can be observed in the proposed new 2D carbon allotropes with tunable bandgaps dependent on the in‐plane biaxial strain. Correspondingly, a pristine 2D carbon sheet with only sp2 hybridization exhibits a promising direct bandgap of 1.062 eV, while the sp3‐hybridized carbon network possesses an indirect bandgap of 1.708 eV, which can be further converted to the direct type under small compressive strains, implying great potential in future carbon‐based nanoelectronic applications beyond graphene. Also, this work provides a new approach for developing novel carbon allotropes via the vertical stacking of graphyne with acetylenic linkages. [ABSTRACT FROM AUTHOR]

Highlights The automotive, aerospace, and sports industries are increasingly utilizing hybrid composites made from natural fiber reinforcements. This study evaluated the performance of a composite made from kenaf and pineapple fibers, manufactured using the compression molding process, with graphene nanoparticles added at varying weight concentrations of 0.5, 1.0, 1.5, and 2.0 wt%. Results showed that adding 0.5 wt% graphene increased the tensile, flexural, and impact strength of hybrid composite by 133.75%, 90.24%, and 25.67%, respectively. Microstructural analysis revealed that graphene integration has enhanced the interfacial bond between the fiber and the matrix, creating resin‐rich areas. Furthermore, the free vibrational analysis indicated that graphene‐infused composites exhibited higher natural frequencies, improving their energy‐absorbing capabilities. Water absorption tests demonstrated that the inclusion of graphene reduced water penetration by improving interfacial bonding, minimizing voids, and decreasing surface energy, which limited water pathways in the composite. Furthermore, the composites with 0.5 wt% graphene showed a contact angle of 80.8°, indicating lower hydrophilicity compared to neat composites, which had a contact angle of 70.7°. This research emphasizes the advantages of hybrid composite materials derived from kenaf and pineapple fibers, specifically for applications in vehicle interiors and construction, including wall panels and separators. Hybrid composite was prepared using the compression molding process. Adding 0.5 wt% graphene improved the mechanical properties of composites. Hybrid composites with lower wt% graphene had higher natural frequencies. The composites with 0.5 wt% graphene had better water absorption properties. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are employed to assess the effects of diverse carbon nanomaterials on the thermo‐oxidative aging properties and tribological behavior of perfluoroelastomer (FFKM) in high‐temperature environments. In this study, carbon nanofillers such as graphene nanosheets (GNS), carbon nanotubes (CNTs), hydroxyl‐functionalized graphene (OH‐GNS), and hydroxyl‐functionalized carbon nanotubes (OH‐CNTs) are examined. The aging properties of composite systems are characterized by parameters like cohesive energy density and mean square displacement. The constant strain method is utilized to estimate the shear modulus and bulk modulus. Three‐layer friction structures are established to analyze the mechanism of fillers on the tribological behavior of composites by applying shear loads. According to the MD simulation results, the addition of carbon nanofillers enhances FFKM's thermo‐oxidative aging performance at 533 K, increases its bulk and shear moduli, and reduces the coefficient of friction and abrasion rate of each composite at high temperatures. Among the four nanofillers, OH‐CNTs is the most effective in terms of improving FFKM performance. Stronger dipoledipole interactions and hydrogen bonding are introduced into the system by OH‐CNTs, which improves the stability of the filler‐matrix interface and produces stronger interfacial interactions. This work offers theoretical predictions for the design and optimization of carbon nanomaterial and FFKM polymer composites. [ABSTRACT FROM AUTHOR]

Chemically modified graphene is an attractive electrode material for electrocatalysis, energy devices, and sensors, whereas pristine graphene is electrochemically passive. The remarkable anisotropic electrochemical nature of graphene is uncovered by π–π interaction, making pristine graphene more active than bare Au. The π–π stacking during redox reaction "dopes" the graphene, disrupting the passivating hydration layer, making it a facile electrochemical electrode. The structure during π–π stacking‐mediated redox of methylene blue (MB) is quantitatively measured by the differential reflectivity of a polarized laser on a ≈100 micron spot. The local redox reaction current varies over fourfold due to the orientation of the ≈10 micron size grains. The mosaic‐grain anisotropy on each spot shows local uniaxial orientation. The redox signal at the optimum orientation is over 2.5‐fold greater than that for bare Au on the same electrode. The redox signal is over fivefold greater at the edges of graphene compared bare Au. Remarkably, the π–π interaction increases chemical stability significantly, leading to negligible photo‐degradation at the approximate absorption wavelength of MB. The exclusive redox activity due to π–π interaction on pristine graphene adds to the toolbox of making exotic opto‐electrochemical electrode materials for electrocatalysis, sensing, and electronics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Graphene nanoribbons (GNRs), which can be considered as a special type of conjugated polymers, are quasi‐one‐dimensional graphene cutouts with an opened band gap, revealing great potential as functional materials in optoelectronic, spintronic, and energy‐related applications. An effective strategy to modulate the properties of GNRs is doping heteroatoms into the π‐skeleton. Thanks to the bottom‐up synthetic approach, a number of heteroatom‐doped GNRs with precise structures have been reported, exhibiting intriguing properties. Nevertheless, a comprehensive summary of the progress of this field has remained elusive. In this review, we summarize the history and advances in bottom‐up synthesized heteroatom‐doped GNRs, including their synthetic routes, electronic properties, and promising applications. We hope to establish the reliable structure–property relationship, and provide guidance for the molecular design of heteroatom‐doped GNRs in the future. [ABSTRACT FROM AUTHOR]

To enhance the inherent poor conductivity and low cycling stability of dimetallic layered double hydroxides (LDHs) materials, designing a synergistic effect between EDLC capacitors and pseudocapacitors is an efficient strategy. In this paper, we utilized a solvothermal technique employing Co‐glycerate as a precursor to prepare sea urchin‐like NiCo‐LDH hollow spheres anchored on a 3D graphene aerogel. The unique morphology of these hollow microspheres significantly expand the specific surface area and exposes more active sites, while reducing the volume changes of materials during long‐term charging and discharging processes. The 3D graphene aerogel serves as a conductive skeleton, improving the material's electrical conductivity and buffering high current. The sea urchin‐like NiCo‐LDH hollow spheres anchored on 3D graphene aerogel (H‐NiCo‐LDH@GA) has a specific surface area of 51 m2 g−1 and the ID/IG value is 1.02. The H‐NiCo‐LDH@GA demonstrate a significant specific capacitance of 236.8 mAh g−1 at 1 A g−1, with a remarkable capacity retention rate of 63.1 % even at 20 A g−1. Even after 8000 cycles at 10 A g−1, the capacity retention still remains at 96.3 %, presenting excellent cycling stability. [ABSTRACT FROM AUTHOR]

With the improvement of radar absorption performance requirements, the research of absorbing materials is an important research direction. In this paper, a graphene/glass fiber/epoxy (GN/GF/EP) structure design scheme is proposed. By measuring the electromagnetic parameters, the influence of different GN content on the absorber performance is analyzed, and the bilayer absorber material combination with the best absorber performance is determined. The double layer absorbing material was made of GN/GF/EP-1.0% (thickness 0.4 mm) and GN/GF/EP-2.5% (thickness 1.7 mm). The peak reflection loss of the double layer absorbing material is −41.55 dB, the center frequency is 10.93 GHz, and the effective absorption bandwidth is 2.86 GHz (9.34∼11.20 GHz). [ABSTRACT FROM AUTHOR]

AbstractThe present investigation focuses on the synthesis of mono (AA5052/SiC and AA5052/graphene) and hybrid (AA5052/SiC/graphene) surface composites using friction stir processing (FSP). This work examines the synergistic effect of SiC and graphene on the fabricated surface composites. Macro/microstructure, microhardness, and wear test analysis were done on these samples, and the results were compared with the base material AA5052-H32. The microstructure analysis showed that the distribution of reinforcement particles in the aluminum matrix is made more uniform by adding hard SiC with graphene nanoparticles, which can reduce the occurrence of particle clustering and agglomeration. As a result, the smallest grain size of 11.2 µm and the highest microhardness obtained was 84.1 HV obtained in hybrid surface composites. Consequently, the hybrid surface composites obtained more improved wear properties than mono surface composites. Thus, the hybrid surface composites achieved the lowest average friction coefficient of 0.304. [ABSTRACT FROM AUTHOR]

Highlights Considering their simplicity, processibility, and tunable rheological properties, polymer composite‐type precursors hold exceptional promise in the processing of polymers, ceramics, metals, and their composites. This large variety of precursors used in many different applications cover a large compositional space with dramatically varying rheological properties. Understanding how precursor composition influences their rheological properties is a key need towards streamlining the design and implementation of these precursors. With regard to this design advancement, this study elucidates the composition‐rheology relationships of graphene‐poly(ethylene) oxide (PEO) composite inks as a sample polymer composite‐type precursor. To this end, shear and extensional rheology of numerous compositions were studied across a wide compositional space, which varied graphene concentration, total solid concentration, and binder molecular weight. These studies showed that composition greatly affected various rheological parameters, such as the overall presence of yielding behavior. Specifically, this study illustrated the influence of (i) binder structure, (ii) total solid loading, and (iii) binder‐filler interactions on ink rheology. Extensional rheology was studied to examine how relaxation behaviors were dependent on composition and explicate how relaxation behaviors coincide with responses to shear forces. In tandem, our results illuminate significant composition‐rheology relationships in polymer composite‐type precursors. Rheology of polyethylene oxide‐graphene composite precursors were studied. Shear and extensional rheology, and their correlations were investigated. Composition‐binder molecular weight‐yielding relationships were elucidated. Extensional relaxation regimes were identified with respect to composition. Results can be used to determine compositional ranges for different processes. [ABSTRACT FROM AUTHOR]

Highlights To improve the thermal conductivity and mechanical properties of graphene‐acrylonitrile butadiene‐styrene plastic (ABS) composite, sub‐phosphite‐based ionic liquid (IL) was synthesized, and its structure was characterized by FTIR, NMR, and mass spectrometry. IL was as a modifier, and graphite powder (G powder) was modified by the ball milling method to obtain functional graphene thermal conductive filler (G‐IL). The structure and morphology of G‐IL were characterized by FTIR, X‐ray photoelectron spectroscopy (XPS), XRD, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the Molau test showed that the presence of IL improved the interfacial interaction of G‐IL and ABS, enhanced the dispersion of G‐IL in the ABS matrix, made G‐IL contact with each other, and it was easier to establish a thermal conduction network and promote phonon transfer. The thermal conductivity of 9 wt% G‐IL/ABS composite was 0.392 W·m−1·k−1, which was 96% and 14% higher than that of pure ABS and G/ABS composite, respectively. The tensile strength and bending modulus of 9 wt% G‐IL/ABS composite were 44.89 and 2124.37 MPa, which were 13% and 11% higher than those of pure ABS, respectively. The impact strength of 9 wt% G‐IL/ABS composite was 34.17 kJ/m2. It was 18% and 7% higher than that of pure ABS and 9 wt% G‐IL/ABS, respectively. Phosphorus imidazole ionic liquids were prepared. Graphene was modified by ionic liquids through non‐covalent. Enhanced mechanical properties and thermal conductivity of G‐IL/ABS composites. [ABSTRACT FROM AUTHOR]

Thermally conductive polymer composites hold great potential for thermal management applications in the electronics industry, but achieving metal‐like thermal conductivity (>200 W m−1 K−1) remains challenging due to the inevitable phonon scattering and the thermal resistance at filler‐filler and filler‐matrix interfaces. Herein, an efficient approach is presented to overcome this long‐standing barrier by designing a densified interconnecting filler framework, featuring a macro‐level carbon fiber (CF) array welded with a high‐quality, self‐assembled graphene network. In this framework, vertically aligned continuous CFs function as primary through‐plane thermal conduction paths, minimizing phonon scattering and thermal resistance. Meanwhile, the secondary graphene network interconnects the CFs into a more integrated and densified framework while introducing supplementary thermal conduction paths. Following polymer backfilling, the resulting epoxy nanocomposite exhibits an unprecedented through‐plane thermal conductivity of 262 W m−1 K−1 at a filler loading of 23.3 vol%, establishing a new benchmark among the thermally conducting polymer composites. When employed as a thermal interface material, this composite offers a 68.2% enhancement in cooling efficiency compared to standard commercial counterparts. Furthermore, the functional composite presents excellent Joule heating and interfacial adhesion properties, making it promising for thermal interface healing and multifunctional thermal management applications in complex environments. [ABSTRACT FROM AUTHOR]

The rising presence of drug-related contaminants in water sources is a major environmental and public health concern. Several studies have addressed the hazardous influence of these pollutants on the lives of over 400 million people worldwide. In this study, we used molecular dynamics simulations to evaluate the efficacy of two promising composite materials for the removal of pharmaceutical contaminants by using the adsorption technique. Graphitic carbon nitride/graphene (g-C3N4/graphene) and metal-organic framework (MIL-101(Fe))/graphene have been simulated for the first time for the removal of three of the most common pollutants (acetaminophen (AC), caffeine (CAF), and sulfamethoxazole (SMZ)). The nanocomposite structure has been created and optimized using the geometry optimization task in the DFTB Modules in the Amsterdam Modeling Suite. We summarized the condition of the essential parameters (Temperature, pressure, and density) of the simulation box during the MD-simulation to ensure the accuracy of our MD-simulation results. The adsorption process, van der Waals interactions, and the adsorption capacity have been calculated by using the Reactive Forcefield (ReaxFF) software. We found that the combination of MIL-101(Fe)/graphene had a higher adsorption capacity for the removal of pharmaceutical contaminants than g-C3N4/graphene. At 40 Picosecond (Ps), 80 molecules of each pharmaceutical contaminants (AC, CAF and SMZ) have been adsorbed by MIL-101(Fe)/graphene with higher exothermic energy equated to (−1174, −1630, and − 2347) MJ/mol respectively. While for g-C3N4/graphene at 40 Ps, 70 molecules of each pharmaceutical contaminants have been adsorbed with exothermic energy equated to (−924, −966, and − 1268) MJ/mol respectively. Also, our results showed that the combination of g-C₃N₄/graphene and MIL-101(Fe)/graphene both have remarkable properties that make them effective at resisting surface clogging. Finally, the results showed that the adsorption kinetics followed a pseudo-first order model, while the adsorption isotherms for AC, CAF and SMZ adhered to Freundlich model. [ABSTRACT FROM AUTHOR]

Because of the surge in the power density of electronic devices, there is an urgent need for improvements in the thermal conductivity of packaging materials. Nowadays, epoxy composites supplemented with thermally conductive fillers are widely used for this purpose, but unfortunately, none of them can satisfactorily meet industrial requirements. Herein, this article reports on a novel method to prepare well‐shaped and highly ordered graphene‐epoxy composite architecture; that is, the epoxy infiltrates into tubular graphene columns that have been restored to the high thermally conductive structure of graphene. As a result, the newly developed graphene‐epoxy composite exhibits record‐high thermal conductivity of 69.74 W m−1 K−1 with filler content of only 11.22 wt.%. The unprecedentedly high thermal conductivity stems from the construction of thermally conductive channels and restoration of the inherent π–π conjugate structure of graphene. These findings not only offer a breakthrough in packaging materials with significantly enhanced thermal conductivity but also provide a promising avenue for the development of other advanced graphene‐added composites. [ABSTRACT FROM AUTHOR]

The dynamical Franz-Keldysh effect, indicative of the transient light-matter interaction regime between quantum and classical realms, is widely recognized as an essential signature in wide bandgap condensed matter systems such as dielectrics. In this theoretical study, we applied time-resolved transient absorption spectroscopy to investigate ultrafast optical responses in graphene, a zero-bandgap system. We observed in the gate-tuned graphene that the massless Dirac materials notably enhance intraband light-driven transitions, significantly leading to the giant dynamical Franz-Keldysh effect compared to the massive Dirac materials, a wide bandgap system. In addition, employing the angle-resolved spectroscopy, it is found that the unique polarimetry orientation, i.e., perpendicular polarizations for the pump and the probe, further pronounces the optical spectra to exhibit the complete fishbone structure, reflecting quantum pseudospin natures of Dirac cones. Our findings expand the establishment of emergent transient spectroscopy frameworks into not only zero-bandgap systems but also pseudospin-mediated quantum phenomena, moving beyond dielectrics. [ABSTRACT FROM AUTHOR]

There is great interest in developing advanced electrical conductors with higher conductivity, lighter weight, and higher mechanical strength than copper (Cu). One promising candidate is copper‐graphene (Cu‐Gr) composite, which is hypothesized to have a higher electrical conductivity than Cu. In this work, it is shown that this is not true, supported by state‐of‐the‐art first‐principles calculations of electron transport. Particularly, contrary to the belief that graphene in the composite is more conductive than pristine Cu, it is less conductive due to increased scattering despite increased carrier concentration. On the other hand, it is found that compressive strain along the (111) plane increases the conductivity, which is confirmed experimentally, while tensile strain has little effect. The work offers new insights into understanding and developing advanced conductors. [ABSTRACT FROM AUTHOR]

Combining Pd with oxophilic species and appropriate catalyst supports is regarded as an effective approach to strengthen the intrinsic electrocatalytic performance of ethanol oxidation reaction (EOR). In this work, palladium nanocrystals (NCs) modified with Bi (OH) 3 were successfully immobilized on the three-dimensional nitrogen-doped graphene (Pd–Bi(OH) 3 /NG) via a simple one-pot route. The resulting Pd–Bi(OH) 3 /NG demonstrates exceptional electrocatalytic performance for EOR under alkaline conditions, exhibiting enhanced mass and specific activity, kinetics, durability and long-term stability, significantly surpassing that of commercial Pd/C. Notably, the electrocatalytic performance of Pd–Bi(OH) 3 /NG-2 (with an atomic ratio of Pd/Bi at 7:1) is the best among all the tested electrocatalysts. The results reveal that the improved electrocatalytic activity of Pd–Bi(OH) 3 /NG may stem from the significant contributions of the Bi(OH) 3 species decorating of the Pd NCs and their incorporation into the nitrogen-doped graphene. • Pd NCs with surface decoration of Bi(OH) 3 species anchored on NG was firstly fabricated. • The Pd–Bi(OH) 3 /NG achieves a superior electrocatalytic performance for alkaline EOR. • The exciting EOR behavior is owing to surface decoration of Bi(OH) 3 around Pd NCs. • The exciting EOR behavior is also derive from the embedding into NG. [ABSTRACT FROM AUTHOR]

PdO is often used to adsorb hydrogen from the desorption of the material in the annular space of cryogenic vessels. However, due to the rarity of palladium in nature, it is particularly necessary to design an efficient hydrogen adsorbent. Alkynylated graphene oxide (AGO) serves as the basis for PdO in AGO-PdO nanocomposites. AGO-PdO is then mixed with alkynylated polyvinyl alcohol (Alkyne-PVA) to form AGO-PdO-(Alkyne-PVA) nanocomposites through self-assembly and grinding methods, respectively. The microstructure and morphology of AGO-PdO and AGO-PdO-(alkyne-PVA) nanocomposites are characterized, and hydrogen adsorption performance are tested. The results show that AGO is an excellent basis for loading PdO nanoparticles. The AGO-PdO-(Alkyne-PVA) nanocomposites prepared by grinding demonstrate a significant enhancement in adsorption performance. In contrast, the AGO-PdO-(Alkyne-PVA) nanocomposites prepared by the self-assembly method exhibit a markedly inferior adsorption performance, which can be attributed to the encapsulation of the PdO nanoparticles by alkynylated polyvinyl alcohol. [Display omitted] • AGO is an excellent basis for loading of PdO. • AGO-PdO-(Alkyne-PVA) nanocomposites prepared by the grinding method showed an excellent adsorption performance. • The multiple use of the precious metal palladium. [ABSTRACT FROM AUTHOR]

Si/graphene nanocomposite is regarded as an advanced lithium-ion anode material, attributable to its advantageous microstructure and exceptionally high theoretical specific capacity. This study demonstrates a novel approach for the preparation of Si/graphene nanocomposites, achieved through the pulsed discharge method employing graphite and Si strips as precursors. We devised two distinct "one-step" synthetic routes through pulsed discharge of different wire arrangements. The characterization results of the obtained samples unveiled the presence of Si/graphene composite and Si@carbon layer composite. In addition, the formation mechanisms of Si/graphene nanocomposites have been proposed, different wire arrangements lead to the different energy deposition processes, inducing different robust mechanical and thermal effects on the products. The formed Si clusters either deposit on the surface of exfoliated graphene or become encapsulated within curling graphitic layers, forming a core@shell structure. This work not only presents a straightforward and innovative approach for synthesizing Si/graphene nanocomposites but also contributes valuable insights into the underlying mechanisms governing their formation. [ABSTRACT FROM AUTHOR]

The present study aims to improve the mechanical strength of hydrogels via a simplified method, involving the creation of a nanocomposite hydrogel using polyvinyl alcohol (PVA) incorporated with un‐modified multiwalled carbon nanotubes (um‐MWCNTs). Departing from conventional freezing–thawing cycles, our research employs a facile approach, in which high‐shear mixing along with solvent exchange with deionized water was utilized. Morphological analysis unveiled a compact and dense microstructure within the nanocomposite hydrogel in correlation with MWCNT concentration. Attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR) elucidated the chemical structure of PVA/um‐MWCNTs hydrogel nanocomposite. Rheological studies on the viscoelastic properties indicated the formation of more "solid‐like" structure in the developed hydrogel nanocomposite. Broadband dielectric spectroscopy revealed alterations in dielectric properties of the fabricated PVA/um‐MWCNTs hydrogel nanocomposite corresponding to MWCNTs content in the PVA matrix. This comprehensive investigation highlights the impact of minimal MWCNTs concentration on the rheology, mechanical, and dielectric properties of developed PVA/um‐MWCNTs hydrogel nanocomposite. [ABSTRACT FROM AUTHOR]

The influence of mixed ion‐electronic conductive fillers on the physical characteristics of protonated polyaniline (P‐PANI) nanocomposite films is investigated by incorporating titanium nanoparticles (TiNPs) and lithium trifluoromethanesulfonate (LiOTf) at various concentrations. The introduction of TiNPs into the P‐PANI matrix results in the appearance of additional X‐ray diffraction peaks ascribed to a titanium phase, confirming the presence of TiNPs. The incorporation of LiOTf leads to changes in intensities, linewidths, and diffraction angles, indicating interactions between Li+ ions and nitrogen atoms in the PANI matrix. The bandgap energy for the pristine P‐PANI film is 3.40 eV, being reduced to 3.29 eV upon incorporating TiNPs in the P‐PANI matrix. An increase in the concentration of LiOTf in the P‐PANI/TiNPs composite films with decreasing TiNPs concentration leads to a continuous increase in bandgap energy to 3.59 eV. The electrical conductivity of pristine P‐PANI is 0.49 mS/cm. The addition of TiNPs increases the conductivity to 2.16 mS/cm, while the addition of LiOTf increases it to 1.72 mS/cm. Notably, (P‐PANI)/TiNPs nanocomposite films with 7:3 and 5:5 wt.% ratios exhibit superior electrical conductivity compared with individual (P‐PANI)/TiNPs and (P‐PANI)/LiOTf films, attributed to effective ionic‐electronic coupling at phase‐separated region interfaces. This study reveals impact of TiNPs and LiOTf on the structural, optical, and electrical properties of P‐PANI nanocomposite films, thereby enhancing their potential for integration into advanced electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Precision chemistry of synthetic carbon allotropes including fullerene and graphene, characterized by a well‐controlled and spatially resolved addends bonding, has received widespread attention owing to its capability to tailor their physicochemical properties for high‐end applications. In the context of fullerene, particularly endohedral metallofullerenes (EMFs), precision chemistry emphasizes the regioselective binding of a specific number of moieties to the fullerene cage. In the case of graphene, precision chemistry focuses on achieving precise patterning and tailored modifications. Inspired by their intriguing advantages, the precision chemistry of these two members has witnessed rapid advancements. While existing reviews have outlined advancements in the precision chemistry of EMFs and graphene, this review uniquely concentrates on the most recent progress. Finally, the prospects in this field, with a special focus on the potential for creating functional materials through strategically patterned binding of fullerene and graphene networks are envisioned. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of TiO2‐graphene nanocomposites with varying mass ratios of graphene (2.5, 5, 10, 20 wt. %) using a facile and cost‐effective hydrothermal approach. By integrating TiO2 nanoparticles with graphene, a nanomaterial characterized by a two‐dimensional structure, unique electrical conductivity and high specific surface area, the resulting hybrid material shows promise for application in supercapacitors. The nanocomposite specimens were characterized by X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman microscopy, field‐emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Additionally, supercapacitive properties were investigated using a three‐electrode setup by cyclic voltammetry (CV), galvanostatic charge‐discharge (GCD) and electrochemical impedance spectroscopy (EIS) tests. Notably, the TiO2‐20 wt. % rGO nanocomposite exhibited the highest specific capacitance of 624 F/g at 2 A/g, showcasing superior electrochemical performance. This specimen indicated a high rate capability and cyclic stability (93 % retention after 2000 cycles). Its remarkable energy density and power density of this sample designate it as a strong contender for practical supercapacitor applications. [ABSTRACT FROM AUTHOR]

To investigate the influence of special nanopore shapes on the mechanical properties of graphene at the atomic scale, a suitable nonlinear atomic-scale finite element model (AFEM) is developed based on the Stillinger Weber interatomic potential (SW). The discrete element created is an atomic finite element consisting of ten atoms, which can capture the dominant local and non-local atomistic interactions dictated by the present interatomic potential. Furthermore, the anterior works demonstrated the simplicity and the accuracy of the SW potential compared to the well-known interatomic potentials used in AFEM for predicting the elastic and fracture properties of graphene. The accuracy of the present model is checked by studying the graphene mechanical properties under the tensile and the shear tests, the comparison between our results and those reported in the literature showed a better agreement. The effect of diamond, hexagonal and rectangular nanopores, as well as their orientations on the elastic and fracture properties of graphene under the tensile and shear tests is also studied. Notably, previous literature lacks a comprehensive study on the shear properties of graphene under nanopore shapes. Our results show that the graphene's mechanical properties are more affected by the nanopores oriented perpendicular to the direction of the applied load. Particularly, the nanopores with elongated sharp tip edges, such as the diamond shape, have the greatest impact on graphene's mechanical response. The results show the ability of the present AFEM to investigate the mechanical behavior of graphene in the presence of various nanopore shapes with high precision at reduced computational time compared to its counterparts. Additionally, it offers simplicity and efficiency in studying large-scale systems. [ABSTRACT FROM AUTHOR]

Context: In this work, a new polymeric structure was designed consisting of a nanometric sheet of graphene (G) and a polymethylmethacrylate (PMMA) repeat unit, which was designated as PMMA-G. Three degrees of polymerization of PMMA-G were considered: monomer (PMMA-G1), dimer (PMMA-G2), and trimer (PMMA-G3). The effect of incorporating a nanometric sheet of graphene into the molecular structure of PMMA on the modification of some of its main optical, magnetic, and electrical properties was investigated. Currently, the study presented here is of great relevance since various areas of technology require new materials with specific properties for the development of new devices. The results of our study reveal that the dielectric constant of PMMA is reduced when graphene is incorporated. However, a percentage increase of 14.48% in the refractive index of PMMA when graphene is inserted to form the nanocomposite is observed. It is found that the absolute value of molar magnetic susceptibility of PMMA increases considerably when reinforced with graphene. Finally, when reinforcing PMMA with graphene to obtain the PMMA-G nanocomposite, the electrical resistivity increases by almost an order of magnitude. Methods: We used computational tools under Materials Studio (MS) software. We built a PMMA molecule with three degrees of polymerization, graphene sheet, and polymethylmethacrylate-graphene composite (PMMA-G) was built also with three degrees of polymerization using a concentration of 50% graphene over the PMMA polymer. For each structure, we used computational code DMol3 of MS, which is based on the Density Functional Theory, and the geometry optimization process was carried out to obtain the most stable structures. Finally, using the connectivity indices method together with topological properties of the molecular structures, implemented in Synthia computational code of MS software, we calculated the dielectric constant, magnetic susceptibility, refractive index, and electrical resistivity, for pure PMMA and PMMA-G structures for their three degrees of polymerization. The results were analyzed, and the changes in these properties were discussed in terms of the effect of an electric and magnetic field on the molecular structures of PMMA-G with respect to PMMA. [ABSTRACT FROM AUTHOR]

Graphene nanoplates (GNP) have been found to significantly enhance the strength of titanium and its alloys due to their unique structure and physical properties. However, the use of GNP-strengthened titanium matrix composites is often limited by a loss of ductility, which can hinder their practical application. This article categorizes two approaches to regulate ductility loss: controlling the distribution of GNP in the titanium matrix and optimizing the interface between GNP and titanium matrix. The critical factors in both approaches and the problems to be investigated in depth are also summarized by integrating published research results and related fundamental theories. Controlling the distribution of GNP is a challenging task, particularly in achieving a specific distribution that maintains the ductility of the titanium matrix. The boundary values of the preparation process parameters and the design of new methods are crucial in this regard. To regulate the interface, it is essential to control the degree of interfacial reaction and optimize the interfacial structure. This approach can effectively address the problems of ductility and strength imbalance. Finally, this section summarizes the challenges that must be overcome in order to apply graphene-reinforced titanium-based materials in practical settings. [ABSTRACT FROM AUTHOR]

Energy harvesting is possible through capable energy transfer materials, and one such impressive material is graphene, which has exhibited promising properties like unprecedentedly high theoretical surface area, enhanced electrical conductivity, thermal conductivity, mechanical stability, flexibility, recyclability, and so on. Herein, for the sake of everyone desirous of contributing to the field of graphene materials for high-speed energy storage devices, the fundamentals, analytics, synthesis, prospects, and challenges of energy storage cell design for fast charging of electric vehicles have been reviewed. To overcome the limitations of mechanistic models for energy-storage devices, empiricism conjointly with data-driven machine learning has been quite effective in multiple domains. The limitations in modeling of energy storage devices, in terms of swiftness and accuracy in their state prediction can be surmounted by the aid of machine learning. Conclusively, in the context of energy management, we underscore the significant challenges related to modeling accuracy, performing original computations, and relevant big data generation. This review, by dint of its futuristic insights, will help researchers to develop digital twin approach for sustainable energy management using energy storage technology toward dependable, economic, and scalable optimization processes at the multiple stages of energy conversion and energy management. [ABSTRACT FROM AUTHOR]

3D printing found its way into various medical applications and could be particularly beneficial for dentistry. Currently, materials for 3D printing of occlusal splints lack mechanical strength compared to polymethyl methacrylate (PMMA) used for standard milling of occlusal splints. It is known that print orientation and graphene nanoplatelets (GNP) can increase biaxial strength in a variety of materials. Thus, the aim of this study was to assess if adjustment of print orientation and addition of GNP improve biaxial strength and if they affect cytotoxicity of a 3D printable resin for occlusal splints. Specimens were printed vertically and horizontally with a stereolithography (SLA) printer and multilayered GNP powder was added to the resin at different concentrations. Printed specimens were characterized by Raman spectroscopy, optical profilometer analysis and scanning electron microscopy. Biaxial strength was evaluated by biaxial flexural testing. Cytotoxicity of specimens on L929 and gingival stromal cells (GSC) was assessed by the toxdent test, the resazurin-based toxicity assay and live-dead staining. Horizontally printed specimens showed significantly higher biaxial strength and lower deformation. GNP did not improve biaxial strength and material deformation of 3D-printed resins. None of the specimens were cytotoxic to L929 cells or GSC. Print orientation in SLA printing has a significant impact on biaxial strength and material deformation. 3D printable materials can reach comparable or even improved biaxial strength compared to PMMA when using the optimal print orientation while GNP has no beneficial effects on the biaxial strength of resins for 3D printing of occlusal splints. [ABSTRACT FROM AUTHOR]

Introduction: Pore structure and geometry are crucial in scaffold development for tissue engineering. From this viewpoint, pore geometry characterization methods will aid in understanding the influence of pore structure (pore size and diffusivity) on its properties. These properties determine how oxygen and water enter the scaffold, forming adsorption states. Previous studies showed that the addition of graphene (G) to polycaprolactone (PCL) increased the pore size, and played a significant role in tissue regeneration. Therefore, this study aimed to evaluate pore structure, geometry, and viability that are suitable for osteogenesis. Materials and methods: Morphology, size, and size distribution of PCL and PCL/G scaffolds were measured at concentrations of 1, 2, and 3 wt% G for the pore structure, while the connectivity of the scaffold's pore was analyzed using the geodesic tortuosity. This is essential because these factors promote the viability of osteogenesis-supporting cells. Results and discussion: The results showed that 3 wt% G had a good water diffusivity rate, larger pores, better connectivity, and viability than other concentrations. Conclusion: In conclusion, the presence of G in scaffolds affects the pore geometry and structure. This results in several advantageous effects that support osteogenesis, such as increased water and nutrient uptake, enhanced waste metabolism transport, and increased viability of the cells. [ABSTRACT FROM AUTHOR]

This review paper focuses on the joint toxicity and interaction of carbon-based nanomaterials (CNMs) with co-existing pollutants in aquatic environments. It explores the potential harmful effects of chemical mixtures with CNMs on aquatic organisms, emphasizing the importance of scientific modeling to predict mixed toxic effects. The study involved a systematic literature review to gather information on the joint toxicity and interaction between CNMs and various co-contaminants in aquatic settings. A total of 53 publications were chosen and analyzed, categorizing the studies based on the tested CNMs, types of co-contaminants, and the used species. Common test models included fish and microalgae, with zebrafish being the most studied species. The review underscores the necessity of conducting mixture toxicity testing to assess whether the combined effects of CNMs and co-existing pollutants are additive, synergistic, or antagonistic. The development of in silico models based on the solid foundation of research data represents the best opportunity for joint toxicity prediction, eliminating the need for a great quantity of experimental studies. [ABSTRACT FROM AUTHOR]

Thermal analysis is widely employed for the characterization of nanomaterials. It encompasses a variety of techniques that allow the evaluation of the physicochemical properties of a material by monitoring its response under controlled temperature. In the case of carbon nanomaterials, such as carbon nanotubes and graphene derivatives, thermogravimetric analysis (TGA) is particularly useful to determine the quality and stability of the sample, the presence of impurities and the degree of functionalization or doping after post-synthesis treatments. Furthermore, TGA is widely used to evaluate the thermal stability against oxidation by air, which can be, for instance, enhanced by the purification of the material and by nitrogen doping, finding application in areas where a retarded combustion of the material is required. Herein, we have evaluated key parameters that play a role in the data obtained from TGA, namely, gas flow rate, sample weight and temperature rate, used during the analysis. We found out that the heating rate played the major role in the process of combustion in the presence of air, inducing an increase in the temperature at which the oxidation of CNTs starts to occur, up to ca. 100 °C (from 1 °C min−1 to 50 °C min−1). The same trend was observed for all the evaluated systems, namely N-doped CNTs, graphene produced by mechanical exfoliation and N-doped reduced graphene samples. Other aspects, like the presence of impurities or structural defects in the evaluated samples, were analyzed by TGA, highlighting the versatility and usefulness of the technique to provide information of structural aspects and properties of carbon materials. Finally, a set of TGA parameters are recommended for the analysis of carbon nanomaterials to obtain reliable data. [ABSTRACT FROM AUTHOR]

An interdigital transducer structure was fabricated from multilayer graphene on the surface of the Y Z -cut of a LiNbO3 ferroelectric crystal. The multilayer graphene was prepared by CVD method and transferred onto the surface of the LiNbO3 substrate. The properties of the multilayer graphene film were studied by Raman spectroscopy. A multilayer graphene (MLG) interdigital transducer (IDT) structure for surface acoustic wave (SAW) excitation with a wavelength of Λ = 60 μm was fabricated on the surface of the LiNbO3 crystal using electron beam lithography (EBL) and plasma chemical etching. The amplitude–frequency response of the SAW delay time line was measured. The process of SAW excitation by graphene IDT was visualized by scanning electron microscopy. It was demonstrated that the increase in the SAW velocity using graphene was related to the minimization of the IDT mass. [ABSTRACT FROM AUTHOR]

The applications of nanotechnology in the field of water treatment are rapidly expanding and have harvested significant attention from researchers, governments, and industries across the globe. This great interest stems from the numerous benefits, properties, and capabilities that nanotechnology offers in addressing the ever-growing challenges related to water quality, availability, and sustainability. This review paper extensively studies the applications of several nanomaterials including: graphene and its derivative-based adsorbents, CNTs, TiO2 NPs, ZnO NPs, Ag NPs, Fe NPs, and membrane-based nanomaterials in the purification of drinking water. This, it is hoped, will provide the water treatment sector with efficient materials that can be applied successfully in the water purification process to help in addressing the worldwide water scarcity issue. [ABSTRACT FROM AUTHOR]

The concept of photonic crystals has recently been extended to the time domain and attracted great interest. Unfortunately, realizing photonic time crystals is a challenging task due to the practical difficulty in modulating dielectric constants with large modulation depth. This problem can be resolved using graphene, the conductivity of which is tunable with significantly large contrast. Herein, graphene plasmonic time crystals, as new kinds of photonic time crystals in atomically thin 2D material, are proposed and their optical properties are investigated. Their band structures are analytically calculated and the propagations of graphene plasmons in temporal crystalline structures are numerically evaluated. Periodically driven by temporally modulating the Fermi energy, graphene plasmons exhibit in‐gap amplification and defect‐immune topological edge states, revealing the nature as plasmonic time crystals. Graphene plasmonic time crystals are realized soon after this proposal due to the possibility of modulating its conductivity with large contrast by simple electrical gating. [ABSTRACT FROM AUTHOR]