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This article discusses polyaniline and graphene (PANI/G) nanocomposites synthesized from aniline monomer and different weight percentages of graphene nanoparticles using chemical oxidation method at 0 °c. The characterization of the nanocomposites was conducted using X-ray diffraction (XRD) and scanning electron microscopy (SEM). SEM scans indicated that the PANI and its nanocomposite exhibited a spherical morphology, with particle diameters less than 35 nm, significantly impacted by graphene. The nanocomposite was investigated as a biological sensor, and the constructed sensor demonstrated its effectiveness in detecting glucose at various concentrations. The results indicate that nanocomposites possess significant promise for many biosensor applications.

Among a large number of current biomedical applications in the use of medical devices, carbon-based nanomaterials such as graphene (G), graphene oxides (GO), reduced graphene oxide (rGO), and carbon nanotube (CNT) are frontline materials that are suitable for developing medical devices. Carbon Based Nanomaterials (CBNs) are becoming promising materials due to the existence of both inorganic semiconducting properties and organic π-π stacking characteristics. Hence, it could effectively simultaneously interact with biomolecules and response to the light. By taking advantage of such aspects in a single entity, CBNs could be used for developing biomedical applications in the future. The recent studies in developing carbon-based nanomaterials and its applications in targeting drug delivery, cancer therapy, and biosensors. The development of conjugated and modified carbon-based nanomaterials contributes to positive outcomes in various therapies and achieved emerging challenges in preclinical biomedical applications. Subsequently, diverse biomedical applications of carbon nanotube were also deliberately discussed in the light of various therapeutic advantages.

With the development of the miniaturization of electronic equipment and lightweight weapon equipment, there are new requirements for electromagnetic wave absorption material (EMWAM). EMWAM has outstanding electromagnetic wave absorption properties and lightweight characteristics become an important direction of research. In this study, graphene/g-C 3 N 4 (GGCN) EMWAM was first synthesized in situ by simple heat treatment, in which the g-C 3 N 4 had a porous structure and dispersed on the surface of graphene. The impedance matching of the GGCN was well adjusted by decreasing the dielectric constant and attenuation constant due to the g-C 3 N 4 semiconductor property and the graphite-like structure. The EMW loss mechanism of GGCN was also analyzed by simulating GGCN’s electric field mode distribution and resistance loss power density. The analysis result shows that the distribution of g-C 3 N 4 among GGCN sheets can produce more polarization effects and relaxation effects by increasing the lamellar spacing. Furthermore, the polarization loss of GGCN could be increased successfully by porous g-C 3 N 4 . Ultimately, the EMW absorption property of GGCN is optimized significantly, and GGCN exhibits excellent EMW absorption performance. When the thickness is 2 mm, the effective absorption bandwidth (EAB) can reach 4.6 GHz, and when the thickness is 4.5 mm, the minimum reflection loss (RL min ) at 4.56 GHz can reach −34.69 dB. Moreover, the practical application of EMWAM was studied by radar cross-section (RCS) simulation, showing that GGCN has a good application prospect.

In this paper, design and modeling of a surface plasmon resonance (SPR) sensors using transition metal dichalcogenide (TMDC) 2D nanomaterials such as tungsten sulfide (WS2) and graphene with the improvements of the sensitivity and the figure of merit (FoM) are demonstrated. The proposed sensors are based on Kretschmann configuration for the obtaining of the reflectivity using the transfer matrix method (TMM) and Fresnel equations. A monolayer of nickel (Ni) was added between WS2 layers and graphene layers to enhance the sensitivity (S) and FoM of our proposed sensor. The reported sensor exhibits a good angular sensitivity which is improved to the maximum value of 243.31°/RIU. It is noted the SPR sensor sensitivity changes with the variation of the WS2 and graphene layer numbers. Full width half maximum (FWHM) values are minimized to be 7.15°; then, the FoM is reached to be 34.03 RIU−1 which gives better sensing properties in comparison with other published articles.

Optical fiber-based surface plasmon resonance sensors using, silver layer (Ag), platinum (Pt), and indium tin oxide in addition to 2D nanomaterials such as graphene are presented in this research. In terms of sensitivity (S) and figure of merit (FoM), the performance analysis of the proposed and configured sensor has been demonstrated. The proposed sensors are based on the scheme of Kretschmann for obtaining the transmitted power using the transfer matrix method and the equations of Fresnel. With theoretical and numerical studies, the reported sensor exhibits a good wavelength sensitivity which is improved to the maximum value of 4150 nm/RIU. Full width half maximum values are minimized to be 59 nm and the FoM is optimized to be 70 RIU −1 which gives better sensing properties in comparison with other published articles.

In recent years, the rapid development of portable/wearable electronics has created an urgent need for the development of flexible energy storage devices. Flexible lithium-ion batteries (FLIBs) have emerged as the most attractive and versatile flexible electronic storage devices available. Carbon nanotubes (CNTs) are hollow-structured tubular nanomaterials with high electrical conductivity, large specific surface area, and excellent mechanical properties. Graphene (G) is to some extent comparable to CNTs, because both have unlimited value in flexible electrodes. Herein, a systematic summary of the application of CNT and G in FLIBs electrodes is presented, including different functional applications and services at different temperatures. Furthermore, the effects of electrode structures, including powder, wire-shaped, and film-shaped structures, on electrochemical properties is highlighted. The assembly structures of the FLIBs consisting of CNT and G-based flexible electrodes to realize different functions, including bendability, stretchability, foldability, self-healing, and self-detecting, are systematically reviewed. The current challenges and development prospects of flexible CNT and G-based flexible electrodes and corresponding FLIBs are discussed.

Nano zinc oxide-decorated graphene (G-ZnO) was blended with polyphenylene sulfide (PPS) to improve its tensile, thermal, crystalline, and barrier properties. The properties of neat PPS and PPS/G-ZnO nanocomposites were characterized and compared using various tests, including tensile tests, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, evaluation of Escherichia coli inhibition, and barrier performance. The results demonstrated that G-ZnO played a crucial role in heterogeneous nucleation and reinforcement. When the concentration of G-ZnO was 0.3%, the tensile strength, elongation at break, thermostability, crystallinity, and water vapor permeability coefficients (WVPC) approached their maximum values, and the microscopic morphology changed from the original brittle fracture to a relatively tough fracture. In addition, when G-ZnO was added to PPS at a ratio of 0.3%, the tensile strength, elongation at break, and WVPC of PPS were increased by 129%, 150%, and 283%, respectively, compared to pure PPS. G-ZnO endowed the nanocomposites with antibacterial properties. The improvement in barrier performance can be attributed to three reasons: (1) the presence of G-ZnO extended the penetration path of molecules; (2) the coordination and hydrogen bonds between PPS polymer matrix and G-ZnO nanofiller narrowed the H2O transmission path; and (3) due to its more hydrophobic surface, water molecules were less likely to enter the interior of PPS/G-ZnO nanocomposites. This study provides valuable insights for developing high-performance PPS-based nanocomposites for various applications.

The structural and electronic properties of graphene/graphene-like Aluminum Nitrides monolayer (Gr/g-AlN) heterojunction with and without vacancies are systematically investigated by first-principles calculation. The results prove that Gr/g-AlN with nitrogen-vacancy (Gr/g-AlN-VN) is energy favorable with the smallest sublayer distance and binding energy. Gr/g-AlN-VN is nonmagnetic, like that in the pristine Gr/g-AlN structure, but it is different from the situation of g-AlN-VN, where a magnetic moment of 1 μB is observed. The metallic graphene acts as an electron acceptor in the Gr/g-AlN-VN and donor in Gr/g-AlN and Gr/g-AlN-VAl contacts. Schottky barrier height Φ B , n by traditional (hybrid) functional of Gr/g-AlN, Gr/g-AlN-VAl, and Gr/g-AlN-VN are calculated as 2.35 (3.69), 2.77 (3.23), and 1.10 (0.98) eV, respectively, showing that vacancies can effectively modulate the Schottky barrier height. Additionally, the biaxial strain engineering is conducted to modulate the heterojunction contact properties. The pristine Gr/g-AlN, which is a p-type Schottky contact under strain-free condition, would transform to an n-type contact when 10% compressive strain is applied. Ohmic contact is formed under a larger tensile strain. Furthermore, 7.5% tensile strain would tune the Gr/g-AlN-VN from n-type to p-type contact. These plentiful tunable natures would provide valuable guidance in fabricating nanoelectronics devices based on Gr/g-AlN heterojunctions.

Acrylamide is a chemical that can form in some foods during high‐temperature cooking processes and is a known carcinogen according to the International Agency for Research on Cancer (IARC). Since biscuit consumption is high amongst Iranians, especially children, and there is a risk of exposure to hazardous compounds such as acrylamide, the purpose of this study is to investigate the amount of acrylamide in some types of biscuits. In this study, graphene (G) modified with magnetite (Fe3O4) and sol–gel hybrid tetraethoxysilane methyltrimethoxysilane (TEOS‐MTMOS) or MSPE (magnetic solid phase extraction) and GC/MS (gas chromatography–mass spectrometry) method was used to measure acrylamide. The calibration curve, LOD (detection limit), LOQ (quantification limit), RSD (Relative standard deviation), recovery, and linear r2 (correlation coefficient) were 0–200 ng/g, 19 μg/kg, 58 μg/kg, 9.64%, 96%, and 0.9982, respectively. The results displayed that the highest level was observed in the biscuits sample with cardamom essential oil (9.01 mg/kg) and the lowest level was observed in the saffron biscuits sample (0.15 mg/kg). According to the results, the mean ± SD of all samples was 1.739 ± 0.830 mg/kg, which being higher than 0.35 mg/kg can be higher than the EU (European Union) standard level. Our results also indicated that biscuits containing essential oil (mean = 4.510 mg/kg) were more contaminated than biscuits containing natural additives (mean = 0.806 mg/kg). Monte Carlo simulation results showed the THQ (Target Hazard Quotient) and ILCR (Incremental Lifetime Cancer Risk) associated with exposure to acrylamide via biscuits for adults were 2.52E‐1 and 2.48E‐4; and for children were 8.75E‐1 and 8.47E‐4, respectively. Uncertain analysis of human health risks by consumption of biscuit samples contaminated with acrylamide showed a serious non‐carcinogenic risk (95th percentile; THQ > 1) for children and a carcinogenic risk (ILCR > 1E‐4) for children and adults. Consequently, there is a significant carcinogenic risk from biscuit consumption. The acrylamide level in various Iranian biscuits was measured using the MSPE (graphene (G) modified with magnetite (Fe3O4) and sol–gel hybrid tetraethoxysilane methyltrimethoxysilane (TEOS‐MTMOS))‐GC/MS method.

With the rapid development of industrial automation and power electronics, the requirements for electrical contact materials are increasing. However, traditional electrical contact materials encountered significant bottlenecks in terms of performance enhancement and production environmental friendliness. Therefore, this paper proposes a new material design idea that utilizes π-π interactions between graphene and compounds with conjugated structures in order to achieve uniform dispersion of graphene in the metal matrix and thus enhance the performance of composites. Based on this design idea, we used nicotinic acid, which has a conjugated structure and is safe, as the complexing agent, and successfully prepared high-quality silver-graphene (Ag-G) composite coatings with graphene uniformly dispersed in the metal matrix on copper substrates by composite electrodeposition technique. Subsequently, the mechanical properties of composite coatings were investigated by hardness test and X-ray diffractometer, and the tribological properties of the composite coatings and the comprehensive performance under the current carrying conditions were systematically evaluated by using friction and wear tester and load key life tester. The results show that the Ag-G composite coatings have significant advantages in mechanical, tribological, and current carrying conditions. This result not only verifies the feasibility of the design idea of the material, but also provides a new direction for the research and development of electrical contact materials.