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This study presents a focused investigation into development of high-performance self-healing graphene polymer composites targeted for critical applications in aerospace, automotive, and electronics sectors. The research emphasizes strategic integration of bioinspired approaches and multi-material systems to enhance autonomous repair capabilities of these composites. Specifically, bioinspired strategies are employed to mimic natural healing processes, while multi-material systems combine graphene with tailored polymers and nanoparticles to achieve superior mechanical strength and facilitate the incorporation of customized functionalities within the composite. The incorporation of stimuli-responsive agents within the graphene composite matrix enables rapid and efficient self-healing upon damage. Advanced characterization techniques, including in-situ microscopy and spectroscopy, are employed to gain a deeper understanding of underlying self-healing mechanisms, guiding development of significantly more resilient graphene composites. Additionally, the study addresses critical challenges associated with scalability, durability, and cost-effectiveness, paving way for wider industrial adoption. Real-world applications, such as self-repairing aircraft components and self-healing electronic circuits, are presented to demonstrate substantial market potential and societal benefits of these advanced materials. By leveraging bioinspired design principles and integrating multi-material systems, this research offers a significant contribution to advancement of self-healing graphene polymer composites, promising smarter, more robust, and ultimately more reliable materials for various high-performance applications. HIGHLIGHTS: Enhanced self-healing in graphene composites for aerospace, automotive, and electronics. Stimuli-responsive agents enable rapid healing, nanoscale structuring boosts strength. In-situ microscopy unveils healing mechanisms; improves composite reliability. Improved properties: mechanical, electrical, thermal, in graphene-based materials. Focus on scalability, durability, cost for broader industrial use; real-world applications showcase potential. [ABSTRACT FROM AUTHOR]

Solar‐driven interfacial evaporation is a promising technology for freshwater production from seawater, but salt accumulation on the evaporator surface hinders its performance and sustainability. In this study, we report a simple and green strategy to fabricate a three‐dimensional porous graphene spiral roll (3GSR) that enables highly efficient solar evaporation, salt collection, and water production from near‐saturated brine with zero liquid discharge (ZLD). The 3GSR design facilitates energy recovery, radial brine transport, and directional salt crystallization, thereby resulting in an ultrahigh evaporation rate of 9.05 kg m−2 h−1 in 25 wt% brine under 1‐sun illumination for 48 h continuously. Remarkably, the directional salt crystallization on its outer surface not only enlarges the evaporation area but also achieves an ultrahigh salt collection rate of 2.92 kg m−2 h−1, thus enabling ZLD desalination. Additionally, 3GSR exhibits a record‐high water production rate of 3.14 kg m−2 h−1 in an outdoor test. This innovative solution offers a highly efficient and continuous solar desalination method for water production and ZLD brine treatment, which has great implications for addressing global water scarcity and environmental issues arising from brine disposal. [ABSTRACT FROM AUTHOR]

The patterning of composites with carbon-based additives of nanometer or micrometer size was studied by the precise modification of material surfaces using laser technology. Initially, the composites are electrical insulators, but we can make them conductive by selective patterning; this process allows us to create conductive tracks within seconds, with a sheet resistance that can be adjusted over a wide range, from 108 Ω/sq down to 2.5 Ω/sq. The additives used include graphene nanoplatelets, graphene oxide nanosheets, and aramid fibers. By conducting microscopic and spectroscopic characterizations before and after laser treatment, we can distinguish between two different processes that lead to electrical conduction: (a) localized increase in the concentration of conductive additives or (b) localized reduction and pyrolysis of insulating additives. To demonstrate the versatility and usefulness of this technique in different fields of application, such as automotive, we fabricate three different devices on polyurethane: a heater, a proximity sensor, and an amperometric sensor for detecting biological analytes. [ABSTRACT FROM AUTHOR]

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Abstract Solar‐driven interfacial evaporation is a promising technology for freshwater production from seawater, but salt accumulation on the evaporator surface hinders its performance and sustainability. In this study, we report a simple and green strategy to fabricate a three‐dimensional porous graphene spiral roll (3GSR) that enables highly efficient solar evaporation, salt collection, and water production from near‐saturated brine with zero liquid discharge (ZLD). The 3GSR design facilitates energy recovery, radial brine transport, and directional salt crystallization, thereby resulting in an ultrahigh evaporation rate of 9.05 kg m−2 h−1 in 25 wt% brine under 1‐sun illumination for 48 h continuously. Remarkably, the directional salt crystallization on its outer surface not only enlarges the evaporation area but also achieves an ultrahigh salt collection rate of 2.92 kg m−2 h−1, thus enabling ZLD desalination. Additionally, 3GSR exhibits a record‐high water production rate of 3.14 kg m−2 h−1 in an outdoor test. This innovative solution offers a highly efficient and continuous solar desalination method for water production and ZLD brine treatment, which has great implications for addressing global water scarcity and environmental issues arising from brine disposal.

The research boom regarding graphene and its composites since its great discovery has continued to mount. Due to its superior electrical and thermal conductivities, high mechanical strength and lightweight characteristics, it has become a hugely potential candidate in hydrogen storage, aerospace, high‐performance composite, sensors, new energy batteries, etc. Here we provide a review of the application of graphene composites and extend into the field of transportation packaging to explore the possibilities of their application. The preparation process, mechanical properties and research methods of graphene structure are introduced, and the practical application of graphene‐reinforced composites is listed. The application prospects of graphene composites in packaging and transportation are presented. [ABSTRACT FROM AUTHOR]

Advances in mobile electronics and telecommunication systems along with 5G technologies have been escalating the electromagnetic interference (EMI) problem in recent years. Graphene-based material systems such as pristine graphene, graphene-polymer composites and other graphene-containing candidates have been shown to provide adequate EMI shielding performance. Besides achieving the needed shielding effectiveness (SE), the method of applying the candidate shielding material onto the object in need of protection is of enormous importance due to considerations of ease of application, reduced logistics and infrastructure, rapid prototyping and throughput, versatility to handle both rigid and flexible substrates and cost. Printing readily meets all these criteria and here we demonstrate plasma jet printing of thin films of graphene and its composite with copper to meet the EMI shielding needs. SE over 30 dB is achieved, which represents blocking over 99.9% of the incoming radiation. Graphene and its composite with copper yield higher green index compared to pure copper shields, implying reduced reflection of incoming electromagnetic waves to help reduce secondary pollution. [ABSTRACT FROM AUTHOR]

Developing biocompatible, non-fouling and biodegradable hydrogels for blood-contacting devices remains a demanding challenge. Such materials should promote natural healing, prevent clotting, and undergo controlled degradation. This study evaluates the biocompatibility and biodegradation of degradable poly(2-hydroxyethyl methacrylate) (d-pHEMA) hydrogels with or without reinforcement with oxidized few-layer graphene (d-pHEMA/M5ox) in a long term implantation in rats, assessing non-desired side-effects (irritation, chronic toxicity, immune response). Subcutaneous implantation over 6 months revealed degradation of both hydrogels, despite slower for d-pHEMA/M5ox, with degradation products found in intracellular vesicles. No inflammation nor infection at implantation areas were observed, and no histopathological findings were detected in parenchymal organs. Immunohistochemistry confirmed d-pHEMA and d-pHEMA/M5ox highly anti-adhesiveness. Gene expression of macrophages markers revealed presence of both M1 and M2 macrophages at all timepoints. M1/M2 profile after 6 months reveals an anti-inflammatory environment, suggesting no chronic inflammation, as also demonstrated by cytokines (IL-α, TNF-α and IL-10) analysis. Overall, modification of pHEMA towards a degradable material was successfully achieved without evoking a loss of its inherent properties, specially its anti-adhesiveness and biocompatibility. Therefore, these hydrogels hold potential as blank-slate for further modifications that promote cellular adhesion/proliferation for tissue engineering applications, namely for designing blood contacting devices with different load bearing requirements. Biocompatibility, tunable biodegradation kinetics, and suitable immune response with lack of chronic toxicity and irritation, are key features in degradable blood contact devices that demand long-term exposure. We herein evaluate the 6-month in vivo performance of a degradable and hemocompatible anti-adhesive hydrogel based in pHEMA, and its mechanically reinforced formulation with few-layer graphene oxide. This subcutaneous implantation in a rat model, shows gradual degradation with progressive changes in material morphology, and no evidence of local inflammation in surrounding tissue, neither signs of inflammation or adverse reactions in systemic organs, suggesting biocompatibility of degradation products. Such hydrogels exhibit great potential as a blank slate for tissue engineering applications, including for blood contact, where cues for specific cells can be incorporated. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphene is a new type of two-dimensional carbon material with excellent mechanical strength, high thermal conductivity, high light transmittance and high specific surface area. Its excellent performance makes it suitable for high-performance electronic devices, composite materials, gas sensors and energy storage and other fields, and has broad application prospects, especially its ultra-high thermal conductivity has attracted great interest of scholars at home and abroad. In this study, the heat transfer theory and the heat transfer mechanism of graphene are firstly cited, and three commonly used composite heat transfer fitting models are proposed. Advantages and disadvantages of measurement methods are described. According to the aforementioned theoretical basis, the equilibrium molecular dynamics and non-equilibrium molecular dynamics heat transfer models were used to fit graphene and its composites, and the thermal conductivity of graphene composites was analysed. Finally, the future research directions of graphene thermal conductivity are prospected.

ABSTRACTAdditive manufacturing has revolutionised the production of intricate and complex structures, offering numerous applications across diverse industries. Among the additive manufacturing techniques, VAT photopolymerisation (VP) is a promising method for fabricating intricate structures with smooth surface finishes. However, the inherent limitations of 3D printed structures, such as compromised mechanical strength and conductivity, necessitate the incorporation of filler materials. Graphene, a remarkable two-dimensional carbon material renowned for its exceptional mechanical and electrical properties, emerges as a highly desirable filler of various applications. The review addresses the critical parameters that affect the quality and properties of graphene composites fabricated using VP, including the choice of photopolymer resin, exposure parameters, and pre and post-processing techniques. It also explores the functionalisation of graphene materials, multi-material printing and hybrid composite systems. The resulting graphene composites find applications in various fields, including electronics, aerospace, biomedicine and energy storage. This review presents a comprehensive survey of these applications, highlighting the unique advantages of VP-derived graphene composites. The challenges and future prospects in the field of VP for graphene composites are discussed. These encompass improving printability, achieving enhanced graphene dispersion, and exploring novel hybrid materials and innovative applications.

Bio‐inspired cilium‐based mechanosensors offer a high level of responsiveness, making them suitable for a wide range of industrial, environmental, and biomedical applications. Despite great promise, the development of sensors with multifunctionality, scalability, customizability, and sensing linearity presents challenges due to the complex sensing mechanisms and fabrication methods involved. To this end, high‐aspect‐ratio polycaprolactone/graphene cilia structures with high conductivity, and facile fabrication are employed to address these challenges. For these 3D‐printed structures, an "inter‐cilium contact" sensing mechanism that enables the sensor to function akin to an on‐off switch, significantly enhancing sensitivity and reducing ambiguity in detection, is proposed. The cilia structures exhibit high levels of customizability, including thickness, height, spacing, and arrangement, while maintaining mechanical robustness. The simplicity of the sensor design enables highly sensitive detection in diverse applications, encompassing airflow and water flow monitoring, braille detection, and debris recognition. Overall, the unique conductive cilia‐based sensing mechanism that is proposed brings several advantages, advancing the development of multi‐sensing capabilities and flexible electronic skin applications in smart robotics and human prosthetics. [ABSTRACT FROM AUTHOR]

In this work, a series of graphene-based composite films were prepared via electron beam (EB) or ultraviolet (UV) irradiation. The influence of the graphene content as well as the irradiation dose on the curing behavior and properties of EB/UV-cured graphene composite films was systematically studied. The curing behavior of the composite films was investigated by the double bond conversion rate as well as the gel content, and the properties of the composite films were studied by TGA analysis and tensile tests. For EB-cured graphene composite films, the curing degree increased with the increase in the irradiation dose (60–360 kGy), and the upper and lower surface was uniformly cured. The curing degree and curing depth of the EB-cured films were not affected by the addition of graphene (0.0–5.0 wt.%). Compared to pure resin film, the EB-cured graphene composite film showed enhanced tensile properties. For UV-cured graphene composite films, the curing degree was also enhanced with the increasing irradiation dose, but it decreased significantly with the increase in graphene content (0.0–5.0 wt.%). The curing degrees of upper and lower surfaces of the UV-cured graphene composite film were not uniform, and the curing depth decreased with the increase in graphene concentration. The addition of graphene had an adverse effect on the thermal and mechanical properties of the UV-cured composite film. [ABSTRACT FROM AUTHOR]

The global energy shortage and environmental degradation are two major issues of concern in today's society. The production of renewable energy and the treatment of pollutants are currently the mainstream research directions in the field of photocatalysis. In addition, over the last decade or so, graphene (GR) has been widely used in photocatalysis due to its unique physical and chemical properties, such as its large light-absorption range, high adsorption capacity, large specific surface area, and excellent electronic conductivity. Here, we first introduce the unique properties of graphene, such as its high specific surface area, chemical stability, etc. Then, the basic principles of photocatalytic hydrolysis, pollutant degradation, and the photocatalytic reduction of CO2 are summarized. We then give an overview of the optimization strategies for graphene-based photocatalysis and the latest advances in its application. Finally, we present challenges and perspectives for graphene-based applications in this field in light of recent developments. [ABSTRACT FROM AUTHOR]

The importance of testing for ammonia is underlined by the fact that its adverse effects on the environment, ecosystems and human health are widely acknowledged. However, detecting low concentrations of ammonia at lower temperatures poses a significant challenge. In this study, a two-dimensional tin sulfide (SnS2) combined with graphene was synthesized using a straightforward one-step hydrothermal method, followed by comprehensive characterization and analysis of the material. The SnS2/rGO (reduced graphene oxide) sensors exhibited the best performance at room temperature (25 °C). The composite material effectively reduced the operating temperature and resistance value of the sensor. Notably, the sensor achieved a minimum detectable concentration of 8 ppb of ammonia. The response of the sensor displayed a favorable linear relationship within the concentration range of 25 ppm to 125 ppm for ammonia. This behavior was accompanied by excellent repeatability. In addition, the gas-sensing mechanism of the ammonia sensor is thoroughly analysed. This study contributes to the progress of ammonia detection technology, a vital aspect of environmental monitoring and safeguarding human well-being. [ABSTRACT FROM AUTHOR]

Abstract Bio‐inspired cilium‐based mechanosensors offer a high level of responsiveness, making them suitable for a wide range of industrial, environmental, and biomedical applications. Despite great promise, the development of sensors with multifunctionality, scalability, customizability, and sensing linearity presents challenges due to the complex sensing mechanisms and fabrication methods involved. To this end, high‐aspect‐ratio polycaprolactone/graphene cilia structures with high conductivity, and facile fabrication are employed to address these challenges. For these 3D‐printed structures, an “inter‐cilium contact” sensing mechanism that enables the sensor to function akin to an on‐off switch, significantly enhancing sensitivity and reducing ambiguity in detection, is proposed. The cilia structures exhibit high levels of customizability, including thickness, height, spacing, and arrangement, while maintaining mechanical robustness. The simplicity of the sensor design enables highly sensitive detection in diverse applications, encompassing airflow and water flow monitoring, braille detection, and debris recognition. Overall, the unique conductive cilia‐based sensing mechanism that is proposed brings several advantages, advancing the development of multi‐sensing capabilities and flexible electronic skin applications in smart robotics and human prosthetics.

In this paper, we report a successful one-step synthesis of Co3O4 Nanoparticles/Laser induced graphene (NPs/LIG) composite by using 1064 nm laser with irradiating cobalt salts impregnated basswood slices in air. The prepared Co3O4 NPs/LIG composites show uniformly distributed nanoparticles on the high-quality 3D graphene. It can be directly used as working electrode for electrochemical reactions without the need for extra post-treatment and exhibits remarkable performance for electrocatalytic OER reaction with an overvoltage of 325 mV at current density of 10 mA·cm−2 and Tafel slope of 66.63 mV·dec−1. Due to its great capability of fabrication precision, simplicity and high speed, this technique indicates immense potential in large scale electrochemical micro-sensor manufacture.

Additive manufacturing has revolutionised the production of intricate and complex structures, offering numerous applications across diverse industries. Among the additive manufacturing techniques, VAT photopolymerisation (VP) is a promising method for fabricating intricate structures with smooth surface finishes. However, the inherent limitations of 3D printed structures, such as compromised mechanical strength and conductivity, necessitate the incorporation of filler materials. Graphene, a remarkable two-dimensional carbon material renowned for its exceptional mechanical and electrical properties, emerges as a highly desirable filler of various applications. The review addresses the critical parameters that affect the quality and properties of graphene composites fabricated using VP, including the choice of photopolymer resin, exposure parameters, and pre and post-processing techniques. It also explores the functionalisation of graphene materials, multi-material printing and hybrid composite systems. The resulting graphene composites find applications in various fields, including electronics, aerospace, biomedicine and energy storage. This review presents a comprehensive survey of these applications, highlighting the unique advantages of VP-derived graphene composites. The challenges and future prospects in the field of VP for graphene composites are discussed. These encompass improving printability, achieving enhanced graphene dispersion, and exploring novel hybrid materials and innovative applications. [ABSTRACT FROM AUTHOR]

This study comprehensively evaluates the thermal upheaval buckling of a functionally graded porous (FGP) pipeline laid on an arched concave seabed. The FGP pipeline is consolidated by graphene platelets (GPL). Symmetric schemes are used for both the pores and the GPL in the thickness direction of the pipeline. The energy method and thin-walled shell theory are adopted to develop analytical frameworks for the thermal instability of the FGP-GPL pipeline. Subsequently, the present results are contrasted with other closed-form solutions, which fully verify the feasibility of this study. Finally, a parametric analysis is conducted, emphasizing the critical temperature variations induced by diverse arch radius, porosity coefficients, graphene weight ratio, and geometric properties of the GPL. It has been found that the thermal stability of the FGP-GPL pipeline is improved by adding more anchors in a certain seabed and laying the pipeline in an arched concave seabed, respectively. The main novelties of the present work are summarized as: (1). develop analytical schemes to provide design guidance for practical applications as an FGP-GPL pipeline lays on an arched concave seabed; and (2). plot explicitly thermal equilibrium curves to illustrate the stability mechanism of an FGP-GPL pipeline laid on an arched concave seabed, respectively. • The FGP-GPLs pipeline deforms radially at a minimum temperature variation. • The critical temperature variation is predicted for the pipeline laid on the arched seabed. • Explicit equilibrium curves are illustrated for the pipeline laid on the arched seabed. • The arched seabed is helpful to resist the thermal buckling of the FGP-GPLs pipeline. [ABSTRACT FROM AUTHOR]

In this manuscript, we have theoretically reanalyzed data prepared and already published by Foroughi et al. (RSC Adv 2016;6:46427–32). These data concern the thermal energy dependence of the electrical conductivity of the samples: graphene fiber, graphene/poly(3,4-ethylenedioxythiophene) (graphene/PEDOT), graphene/carbon nanotube (graphene/CNT) and graphene/carbon nonotube/poly(3,4-ethylenedioxythiophene) (graphene/CNT/PEDOT) composite fibers. We investigate the behavior of the thermal conductivity for these four samples. These samples are considered as thermoelectric materials or green energy conversion materials using the Seebeck effect to transform heat into electrical energy and vice versa. In this context, the optimization of the merit factor ZT remains a challenge for the scientific community. The objective of this investigation is to evaluate and characterize the thermoelectric efficiency of the above-mentioned samples. We confront the experimental data with the existing theoretical models. The thermoelectric efficiency is generally characterized by the merit factor ZT. The maximum ZT of about 1,2 is obtained in the graphene fiber and between 0,1 and 0,2 in the others samples. The performance of the material depends on ZT; indeed a high ZT (⁠|$\mathrm{ZT}\ge 1$|⁠) corresponds to a better optimization of the composite. [ABSTRACT FROM AUTHOR]

The effect of the filler content and concentration on the structural, electrical, mechanical, and electromagnetic interference shielding effectiveness (SE) is reported in epoxy (Ep)/Graphene (Gr)/Nickel ferrite (NiF) based hybrid composite. The paper also presents the use of nickel ferrite in achieving magnetic alignment using a low magnetic field (0.165 T). The effect of magnetic alignment on the properties of the composites is also studied. The graphene content in Ep/Gr composite is varied systematically to obtain electrical percolation. A percolation threshold value of 1% was obtained using a simple solution-based processing technique. The dielectric and magnetic loss enhancement with the addition of magnetic nanoparticles of nickel ferrite was attempted. Dielectric and magnetic loss is studied based on the permittivity and permeability measurement in the frequency range 8.2–12.4 GHz. Total SE in this frequency range is studied and the effect of the filler content and magnetic alignment on SE is discussed. [ABSTRACT FROM AUTHOR]

Research on the synthesis of water-soluble polymers has accelerated in recent years, as they are employed in many bio-applications. Herein, the synthesis of poly[2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (PSB) by free radical polymerization in a sonication bath is described. PSB and iron oxide nanoparticles (IONPs) were simultaneously stabilized on the graphene surface. Graphene surfaces with PSB (GPSB) and graphene surfaces with PSB and IONPs (GPSBI) were prepared. Since PSB is a water-soluble polymer, the hydrophobic nature of graphene surfaces converts to hydrophilic nature. Subsequently, the prepared graphene composites, GPSB and GPSBI, were well-dispersed in water. The preparation of GPSB and GPSBI was confirmed by X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The impacts of PSB and IONPs on the graphene surfaces were studied systematically. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a public health concern because of its carcinogenic, teratogenic and immunotoxic nature, thus sensitive and selective monitoring of this molecule in food samples is of great importance. Herein, we report the development of a highly sensitive and selective electrochemical aptasensor using electrospun cellulose acetate (CA)-doped three-dimensional (3D)-graphene for OTA determination. The free-standing electrospun CA/3D-graphene surface was functionalized with silane and glutaraldehyde functional groups to tether terminal linkers for immobilizing OTA aptamer using the layer-by-layer deposition method. The current–voltage measurements of the proposed aptasensor revealed a low detection limit of 156 fg ml−1 and sensitivity at 0.3 nA with a linear detection range of 1 fg ml−1 to 1 ng ml−1. This aptasensor did not show an interference effect during the selectivity test in the presence of other mycotoxins. The excellent applicability of the developed aptasensor has been verified in paddy rice-spiked samples, showing great potential in fields of food safety. The improved performance of this aptasensor is attributed to the large surface area, interconnected and porous structures of the electrospun fibrous membrane as well as the synergetic effect between graphene and the CA polymeric nanofibres, which creates a suitable matrix for aptamer immobilization and OTA interactions. The proposed aptasensor exhibits excellent sensitivity, selectivity, and thus could be a promising strategy for efficient on-site detection of OTA in food safety control and environmental monitoring. [ABSTRACT FROM AUTHOR]

Conductive graphene polymer composites are considered promising functional materials in gas detection, strain detection, metal corrosion prevention, and electromagnetic wave absorption, owing to their good flexibility, lightweight, and adjustable conductivity. The internal defects or external damages of composite films will seriously affect the electrical and functional properties of the materials. Based on the conductive network inside the conductive polymer film and the self-inductance to ultrasonic wave, the defect self-monitoring system of the conductive polymer film is designed and optimized in this work. The self-damage detection system is composed of an electrode array, excitation source, resistance signal acquisition and processing circuit, and damage display. Aiming at different scenarios, the improved interdigital structure transducer for sensors and damage detection device for coating film with a large area are presented and optimized respectively. Meanwhile, the damage location algorithm based on time difference measurement and kernel density estimation algorithm is also optimized. The multiple damage detection is realized by a device with a 4 × 8 electrode array, and the relative error of damage area with 1 mm × 1 mm is less than 5%, and the lower detection limits of damage size are 0.3 mm × 0.3 mm. [ABSTRACT FROM AUTHOR]

The global energy shortage and environmental degradation are two major issues of concern in today’s society. The production of renewable energy and the treatment of pollutants are currently the mainstream research directions in the field of photocatalysis. In addition, over the last decade or so, graphene (GR) has been widely used in photocatalysis due to its unique physical and chemical properties, such as its large light-absorption range, high adsorption capacity, large specific surface area, and excellent electronic conductivity. Here, we first introduce the unique properties of graphene, such as its high specific surface area, chemical stability, etc. Then, the basic principles of photocatalytic hydrolysis, pollutant degradation, and the photocatalytic reduction of CO2 are summarized. We then give an overview of the optimization strategies for graphene-based photocatalysis and the latest advances in its application. Finally, we present challenges and perspectives for graphene-based applications in this field in light of recent developments.

The broad applications of graphene-based scaffolds demand fabrication methods that are simple and yet can create complex architectures. This is particularly true for bone tissue engineering, where interconnected, micro and macro porosity is required for cell penetration and nutrient exchange. Here, a dual-templating method is developed to produce graphene oxide (GO) scaffolds with interconnected hierarchical porosity: upon freezing and drying high internal phase emulsions exclusively stabilized by GO sheets, large pores are templated by the oil droplets, and small pores by ice crystals formed in the water phase, whose size can be controlled by freezing temperature. The resulting scaffolds are excellent substrates for mesenchymal stem cell penetration and growth. This method also enables the synthesis of complex hierarchical architectures in reduced graphene oxide (rGO) and GO composite scaffolds, through a single, versatile strategy. [Display omitted] [ABSTRACT FROM AUTHOR]

Stretchable electrodes are more suitable for dielectric elastomer transducers (DET) the closer the mechanical characteristics of the electrodes and elastomer are. Here, a solvent‐free synthesis and processing of conductive composites with excellent electrical and mechanical properties for transducers are presented. The composites are prepared by in situ polymerization of cyclosiloxane monomers in the presence of graphene nanoplatelets. The low viscosity of the monomer allows for easy dispersion of the filler, eliminating the need for a solvent. After the polymerization, a cross‐linking agent is added at room temperature, the composite is solvent‐free screen‐printed, and the cross‐linking reaction is initiated by heating. The best material shows conductivity σ = 8.2 S cm–1, Young's modulus Y10% = 167 kPa, and strain at break s = 305%. The electrode withstands large strains without delamination, shows no conductivity losses during repeated operation for 500 000 cycles, and has an excellent recovery of electrical properties upon being stretched at strains of up to 180%. Reliable prototype capacitive sensors and stack actuators are manufactured by screen‐printing the conductive composite on the dielectric film. Stack actuators manufactured from dielectric and conductive materials that are synthesized solvent‐free are demonstrated. The stack actuators even self‐repair after a breakdown event. [ABSTRACT FROM AUTHOR]

Graphene ferrites have attracted great attention due to their high conductivity and large specific area. Now, the modern age demands some new materials which have a low weight, less cost and have great mechanical strength. Graphene is the best suggestion to meet this criteria. Here, graphene oxide (GO) was synthesized with Hummer's method. Prussian Blue (PB) and Fe 3 O 4 nanoparticles were doped in graphene oxide with the Massart method. XRD spectra were used to analyze the structural properties. Peaks of XRD spectra at 2θ = 24.16°, 30.01°, 35.27°, 39.29°, 43.37°,53.82°, and 57.14° confirmed the formation of PB and Fe 3 O 4 nanoparticles in graphene oxide. Electronic transition properties were studied through UV–visible spectroscopy and a peak of π to π* transition is detected at 198.9 nm in PBGOF. Due to charge transformation between carbon network, magnetite and PB, the strong shifted peak is detected in PBGOF in PL spectra at 439.2 nm. At lower frequency the dielectric properties exhibit higher values of permittivity and vary as a function of frequency. Electrical properties investigated through impedance spectroscopy and material show increment in electrical behavior. AC resistivity exhibit the small resistance and high conductive properties of the material with the increase of frequency. There is an expectation that with the introduction of magnetite in Graphene, the dielectric properties enhanced dramatically. Our finding revealed that our material has many possible applications in electrical and electronic devices etc. [ABSTRACT FROM AUTHOR]

A problem of damping vibrations of a smart structure consisting of elastic and viscoelastic materials and piezoelements with connected shunt circuits is considered. It is proposed to replace the classical resistor in the shunt circuit by an element made of an electroconducting material, in particular, a polymer material filled with graphene nanoparticles. This element plays the role of several resistors with different resistance values, which ensure multimodal damping of vibrations. A mathematical formulation of the problem of forced steady-state vibrations and natural vibrations of smart systems under consideration is provided, as well as results of numerical calculations, which show that graphene-based composites can be used for additional damping of vibrations of smart structures based on piezoelements. [ABSTRACT FROM AUTHOR]

Conductive graphene polymer composites are considered promising functional materials in gas detection, strain detection, metal corrosion prevention, and electromagnetic wave absorption, owing to their good flexibility, lightweight, and adjustable conductivity. The internal defects or external damages of composite films will seriously affect the electrical and functional properties of the materials. Based on the conductive network inside the conductive polymer film and the self-inductance to ultrasonic wave, the defect self-monitoring system of the conductive polymer film is designed and optimized in this work. The self-damage detection system is composed of an electrode array, excitation source, resistance signal acquisition and processing circuit, and damage display. Aiming at different scenarios, the improved interdigital structure transducer for sensors and damage detection device for coating film with a large area are presented and optimized respectively. Meanwhile, the damage location algorithm based on time difference measurement and kernel density estimation algorithm is also optimized. The multiple damage detection is realized by a device with a 4 × 8 electrode array, and the relative error of damage area with 1 mm × 1 mm is less than 5%, and the lower detection limits of damage size are 0.3 mm × 0.3 mm.

Graphene has received extensive attention due to its excellent properties, and is considered to have broad application prospects in the fields of material processing, energy, biomedicine and drug delivery. Recently, graphene and its composite materials have been gradually applied to wastewater treatment. Here, different graphene composites and their properties are outlined. The application of graphene and its composites as adsorbents and catalysts in typical wastewater treatment (such as dye wastewater, heavy-metal wastewater, oily wastewater, refractory organic wastewater) is reviewed. The treatment efficiency and treatment mechanism of different graphene composites are summarized and analyzed. Finally, reasonable comments and suggestions are raised about the existing problems in wastewater treatment applications. And the outlook for and the future development of graphene and its composites were discussed. [ABSTRACT FROM AUTHOR]

• TiCN-graphene composites produced by intercalation of ethylenediamine and poly(ethyleneimine) as organic linkers. • TiCN-graphene composites supported Pt nanoparticles for methanol oxidation reaction. • Pt nanoparticles are deposited on top of the TiCN particles. • The mass activity was improved on the graphene composite-supported catalysts. • Ethylenediamine leads to more active and stable catalyst. In the present work, the effect of different composites as electrocatalytic supports for the methanol oxidation reaction is evaluated. Two different TiCN-rGO composites, using organic compounds as linkers were synthesized. Subsequently, platinum was incorporated in the form of nanoparticles, and the electrocatalysts were characterized and compared with similar nanoparticles supported on TiCN. The electrocatalysts were characterized by XPS, TEM, XRD, Raman and FTIR spectroscopies and ICP-MS and the catalytic performance toward CO ads and methanol oxidations was evaluated. Results showed that the platinum nanoparticles were preferentially deposited on top of the TiCN particles rather than on the reduced graphene oxide, which allowed the nanoparticles to benefit from the TiCN electronic promoting effect. In addition, the presence of reduced graphene oxide contributes on the improvement of the morphological properties of the electrocatalyst, reducing the agglomeration degree of the particles and considerably enhancing the catalytic mass activities. [ABSTRACT FROM AUTHOR]

The formation of single-layer and multilayer graphene by chemical vapor deposition has been studied experimentally. The structures of coatings formed at different temperatures and compositions of the gas mixture have been analyzed. Regimes for transferring graphene structures to various substrates have been developed. Transparent flexible conductive polyethylene terephthalate–ethylene vinyl acetate–graphene and polymethylmethacrylate–graphene composites have been obtained. [ABSTRACT FROM AUTHOR]

A desirable counter electrode material for dye‐sensitized solar cells (DSSCs) needs to have superior electrocatalytic activity, low charge‐transfer resistance, and long‐term stability. Herein, the development of a composite of nitrogen‐doped carbon nano‐onions with modified reduced graphene (N‐CNOs/mGr) to achieve these merits is reported. The mGr network has high electrical conductivity to improve charge transfer; the N‐CNOs with pyridinic and graphitic N provide more electrocatalytic active sites for the reduction of I3− to I−, and the carbon composite demonstrates excellent electrochemical stability. The constructed DSSC with the N‐CNOs/mGr electrode presents better long‐term stability and a higher power conversion efficiency of 10.28% than those devices with conventional Pt (6.54%) and mGr (5.11%) electrodes. Therefore, the all carbon‐based composite will open up new opportunities for a variety of electrochemical device applications. [ABSTRACT FROM AUTHOR]

The paper presents the tuning of sensitivity and selectivity performance of volatile organic compounds (VOCs) chemoresistive sensors for biomarker detection using the hybridization of pristine graphene (pG) and metal organic frameworks (MOFs). The synergistic effect of this nanocomposite material was discovered showing improved sensing performances where graphene acts as a highly conductive sensing element, and MOFs, with a high surface area and adsorption capacity provide an enhanced sensitivity and selectivity for specific VOCs. By combining and selecting different MOFs, we proposed that is possible to tailor sensing performances of chemoresistive sensors for VOC biomarkers detection. To prove that graphene hybrid nanocomposite with selected MOFs including copper–benzene-1,3,5-tricarboxylate (pG-Cu BTC), zirconium 1,4-dicarboxybenzene (pG-UiO 66) and 2-methylimidazole zinc salt (pG-ZIF 8), were investigated to enhance the sensing performance and capability of distinguishing different VOC biomarkers (e.g., methanol, ethanol, chloroform, acetone, acetonitrile and THF). Results showed that the pG-Cu BTC sensor has the highest sensitivity and selectivity towards chloroform and methanol VOCs at 2.82–22.6 ppm level. The proposed concept presents a valuable contribution for the development of low-cost and high-performing VOC biomarker sensors for monitoring human health from metabolic human breath and further implementation for non-invasive biomedical diagnostics for personalized telehealth monitoring. Image 10660 [ABSTRACT FROM AUTHOR]

The interface of graphene/epoxy was studied using molecular dynamics simulations by calculating the work of separation and traction-separation responses in the normal mode. The influence of functionalization of the graphene layers on the traction-separation behaviour was also examined by grafting hydroxyl, carboxyl, and carbonyl groups. It is shown that the magnitude of the maximum traction is clearly larger for functionalized graphene/epoxy systems as compared to pristine graphene. The work of adhesion also shows a clear difference in the interface behaviour of functionalized graphene/epoxy and pristine/epoxy systems with the presence of functional groups generating higher values of work of separation. [ABSTRACT FROM AUTHOR]

Carbon nanoallotropes such as carbon nanotubes, graphene, and their derivatives have been combined with a plethora of polymers in the last years to develop new composite materials with interesting properties and applications. However, the area of photopolymer composites with carbon nanostructures has not been analogously explored. In the present article, we study the photopolymerization of poly(ethylene glycol)diacrylate (PEGDA) enriched with different carbon nanoallotropes like graphene, pristine and chemically modified carbon nanotubes (CNTs and fCNTs), and a hybrid of graphene and CNTs. The products were characterized by several microscopic and spectroscopic techniques and the electrical conductivity was studied as a function of the concentrations of carbon nanoallotropes. In general, stable thin films were produced with a concentration of carbon nanostructures up to 8.5%, although the addition of carbon nanostructures in PEGDA decreases the degree of photopolymerization, and PEDGA/carbon nanostructure composites showed electrical conductivity at a relatively low percentage. [ABSTRACT FROM AUTHOR]

A series of novel sandwich-like GO@SiO 2 @C@Ni composites were developed. The morphologies and adsorption capacities of the materials sintered at different carbonization temperatures were investigated. The formed GO@SiO 2 @C@Ni-400 possessed of wonderful dispersion, large surface area (229.88 m2/g) and high saturation magnetization. Batch experimental results revealed that maximum adsorption capacities of these materials towards Cr(VI) were as follows: GO@SiO 2 @C@Ni-400 (299.20 mg/g) > GO@SiO 2 @C@Ni-500 (244.05 mg/g) > GO (202.39 mg/g) > Graphene@C@Ni (188.80 mg/g) > GO@SiO 2 @C@Ni-600 (165.51 mg/g) > GO@SiO 2 @C@Ni-700 (93.36 mg/g). Moreover, the influence of hydrochemistry, such as contact time, pH, co-existing ions and solution temperature, on Cr(VI) adsorption was researched as well. It was demonstrated that GO@SiO 2 @C@Ni-400 had remarkable adsorption capacity for Cr(VI) removal under the acidic condition, hardly disturbed by other anions, and showed better adsorption performance at 328 K. Besides, On the base of X-ray photoelectron spectroscopy analysis, mechanisms of adsorption could be explained that Cr(VI) was reduced to Cr(III) by nitrogen dopant, and the complexation was existed between Cr(VI) and oxygen-containing functional groups. Additionally, GO@SiO 2 @C@Ni-400 could be easily separated under the external magnetic field and displayed outstanding reusability. Herein, GO@SiO 2 @C@Ni-400 opens up the possibility of future practical applications. [ABSTRACT FROM AUTHOR]

A graphene-based magnetic composite (Fe3O4/GO) was prepared and used for simultaneous removal of Cu(II) and 1-naphthol. The composite was characterized by SEM, TEM, XRD, FT-IR and Raman. Electron microscopy reflected that Fe3O4 spheres were dispersed on graphene layers. The pseudo-second-order kinetic and Langmuir isotherm models could best describe the sorption kinetics and isotherms. The sorption of Cu(II) and 1-naphthol increased with increasing temperature, and thermodynamic parameters calculated from temperature dependent sorption revealed that sorption of Cu(II) and 1-naphthol on Fe3O4/GO was spontaneous and endothermic. The results indicated that Fe3O4/GO can be utilized as potential adsorbents for purification of co-contaminated water systems. [ABSTRACT FROM AUTHOR]

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• Recent progresses in fabricating G-BFNs for advanced biological and cellular interfaces are summarized. • Diverse facile and eco-friendly strategies for the synthesis and functionalization of G-BFNs are outlined. • Current developed G-BFNs based on their nanostructures and biofunctionalities have been carefully discussed. • Biointeractions and biocompatibilities at the interfaces of G-BFNs with viruses, bacteria and stem cells are highlighted. • Emerging biological applications and future perspectives of G-BFNs are discussed. Currently, abundant efforts have been devoted to research on graphene in interdisciplinary applications due to their unique physicochemical, electronic and biological properties. Accompanying the rapid developments of graphene, it is highly important to explore graphene based bio-functional nanostructures (G-BFNs) to bridge the gap between the fundamental advantages of graphene and the requirements in designing hybridized biomaterials. Here, this review aims to outline and summarize the recent advancements in fabricating G-BFNs for advanced biological and cellular interfaces. We first discuss the general protocols for the synthesis of G-BFNs, especially diverse facile and eco-friendly strategies. Then, we carefully summarize the current developed G-BFNs based on their nanostructures and biofunctionalities, such as physiologically-stability, stimuli-responsibility, graphene-inorganic nanohybrids, functional nano-inks, nacre-like layered composites, macroporous scaffolds, 3D printed microlattices, and injectable hydrogels. Moreover, biointeractions at the interfaces of G-BFNs with viruses, bacteria and stem cells, and the relevant biocompatibilities are also highlighted. Furthermore, the emerging applications and future perspectives of G-BFNs in nanotherapeutics, anti-pathogens, tissue regeneration, and monitoring biosensors are carefully discussed. We envision that such a timely and cutting-edge review will not only take a step towards the development of G-BFNs but also inspire new opportunities by using emerged nanomaterials for biological and cellular interfaces. [ABSTRACT FROM AUTHOR]

Graphical abstract A high-intensity compact ultrasonic irradiation assisted technique results in novel hierarchically porous N-doped graphene microsheets (PNGTMSs) with a highly interconnected three-dimensional network nanostructure allowing well-dispersion of near-spherical Ni 2 P nanoflowers. High porosity and optimal thickness allow the whole volume of an isolated microsheet in PNGTMSs to be ion-accessible. Combined with good dispersion of Ni 2 P and rich exposed interfaces, the Ni 2 P-PNGTMSs composite shows higher specific capacitances and superior rate capability than most reported similar graphene-based composites. Asymmetric solid-state cell displays a high output voltage of 1.8 V and delivers high energy densities over those reported for similar devices as well as remarkable cycling stability. Highlights • Novel hierarchical PNGTMSs feature the advantages of both 2D and 3D graphene. • Achieved by a high-intensity compact ultrasound assisted technique. • New insights into ultrasonic activation are proposed. • Ni 2 P-PNGTMSs composite shows high capacity, superior rate capability and stability. • Asymmetric supercapacitor achieves high energy density and power densities. Abstract Severe restacking of single-atom-thick two-dimensional graphene and too long ion diffusion path in a thick three-dimensional porous graphene film are both main current problems limiting performance maximization of graphene as an energy storage material. Herein, we report an advance toward the design and fabrication of novel hierarchically porous N-doped graphene thin microsheets (PNGTMSs) with a honeycomb-like network structure allowing good dispersion of near-spherical Ni 2 P nanoflowers (NFs) by high-intensity compact ultrasound assisted technique. New insights into ultrasonic activation inducing a preferential self-assembly in a planar direction are proposed. High porosity and thin thickness of <500 nm allow the whole interior of isolated microsheets to be ion-accessible, which endows PNGTMSs with advantages of both two-dimensional and three-dimensional graphene as well as enhanced electrical conductivity. Combined with Ni 2 P nanosheet-built NFs and their good dispersion as well as rich exposed interfaces, Ni 2 P-PNGTMSs exhibits specific capacitance of 1100 F g−1 at 1.0 A g−1. Asymmetric solid-state device delivers an energy density of 39.8 Wh kg−1 (at 450.6 W kg−1) and remarkable cycling stability with 97% capacitance retention after 5000 charge-discharge cycles. This work provides a convenient and scalable strategy for control over graphene nanostructures and their composites for highly enhanced energy storage. [ABSTRACT FROM AUTHOR]

A combination of wide‐angle X‐ray scattering (WAXS) and pair distribution function analysis was used to investigate the structural changes occurring in beech wood and apricot tree pruning samples during slow and fast pyrolysis up to 1400°C (1673 K). WAXS curve modeling with the program CarbX provides unique information about the arrangement of graphene layers described by intralayer, interlayer, disorder and dispersion structural parameters. Pair distribution function modeling in PDFgui revealed imperfections in single graphene sheets, such as bond shortening and curvature, when refinement is performed in different r ranges. The concentration of inorganic species, along with heating rate, influences the final structure of pyrolysis products. The heating rate was more important than sample composition for an increase in extent of the single graphene layer and average chord length, while the average graphene coherent stack height depended on both composition and heating rate. Higher fractions of inorganic material increased the average interlayer spacing and the number of graphene layers per stack. Atomic level structural changes of pyrolized beech and apricot plant material were modeled using two different approaches: total wide‐angle X‐ray scattering curve fitting and pair distribution function analysis. It is shown that the information obtained from the combination of these two analytical techniques is complementary, while using only one can provide a partial and incomplete view of structural changes. [ABSTRACT FROM AUTHOR]