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At present, the main raw material for producing graphene is graphite ore. However, researchers actively seek alternative resources due to their high cost and environmental problems. Biomass waste has attracted much attention due to its carbon-rich structure and renewability, emerging as a potential raw material for graphene production to be used in sports equipment. However, further progress is required on the quality of graphene produced from waste biomass. This paper, therefore, summarizes the properties, structures, and production processes of graphene and its derivatives, as well as the inherent advantages of biomass waste-derived graphene. Finally, this paper reviews graphene's importance and application prospects in sports since this wonder material has made sports equipment available with high-strength and lightweight quality. Moreover, its outstanding thermal and electrical conductivity is exploited to prepare wearable sensors to collect more accurate sports data, thus helping to improve athletes' training levels and competitive performance. Although the large-scale production of biomass waste-derived graphene has yet to be realized, it is expected that its application will expand to various other fields due to the associated low cost and environmental friendliness of the preparation technique. [ABSTRACT FROM AUTHOR]

The development of new and high-performing electrode materials for sensing applications is one of the most intriguing and challenging research fields. There are several ways to approach this matter, but the use of nanostructured surfaces is among the most promising and highest performing. Graphene and graphene-related materials have contributed to spreading nanoscience across several fields in which the combination of morphological and electronic properties exploit their outstanding electrochemical properties. In this review, we discuss the use of graphene and graphene-like materials to produce gas sensors, highlighting the most relevant and new advancements in the field, with a particular focus on the interaction between the gases and the materials. [ABSTRACT FROM AUTHOR]

Nanomaterials, especially graphene derivatives, have become major tools in the biomedical area. Understanding the way that graphene interacts with component elements of biological systems, like biological membranes, is critical for the development of successful biomedical applications. The interaction mechanism of graphene sheets with a model cell membrane was investigated in this study using molecular dynamics (MD) simulations under three different conditions: pristine graphene (PG), carboxyl group-functionalized graphene (G-COOH), and amine group-functionalized graphene (G-NH2). The MD simulations demonstrated that functional groups on graphene surfaces improve their interaction with the head groups of the membrane. In 200 nanoseconds, PG reached equilibrium outside and near the phospholipid membrane. G-NH2 was positioned away from the model membrane’s surface, while G-COOH and G-NH2 also achieved equilibrium outside the membrane. It was shown by molecular dynamics simulations that after 200 ns, all three systems had attained their stable states. Crucially, it is discovered that the kind of functional groups greatly affected how the nanoparticles and membrane interacted. Each and every nanocarrier has a strong propensity to break through the membrane. The van der Waals interaction energies for the PG, G-NH2, and G-COOH systems were further shown by the obtained data to be roughly −400.66, −397.52, and −876.36 kJ/mol, respectively. These results support the notion that G-COOH interacts with the model cell bilayer more strongly than PG and G-NH2. This work highlights the influence of functional groups on the interaction of graphene sheets with biological membranes, offering important insights into the equilibrium behavior and entry mechanism of graphene sheets in a model cell membrane.

Fluorographene exhibits a rich chemistry and a wide range of applications in energy storage devices. This review, which is based on our lab results acquired in the last decade, explores the synthesis, properties, and performance of fluorographene-based materials in supercapacitors and batteries. Fluorographene can be prepared through mechanical or chemical delamination of graphite fluoride, allowing for scalable synthesis and further chemical processing. The chemical versatility of fluorographene enables a wide portfolio of chemical reactions, leading to a new class of graphene derivatives. Graphene acid, a product of fluorographene chemistry, exhibits excellent specific capacitance, cycling stability, and rate capability. Hybridizing graphene acid with metal-organic frameworks can achieve even higher energy and power densities. Furthermore, nitrogen-doped graphene derived from fluorographene demonstrates remarkable capacitive behavior, making it an efficient electrode material for supercapacitors. Additionally, fluorographene-based materials, such as graphene acid, graphene-sulfur hybrids, and graphene-based anodes, have exhibited outstanding performance in lithium-ion and lithium-sulfur batteries. The scalable synthesis, high performance, and versatility of fluorographene-derived materials render them attractive for practical energy storage applications. The unique properties and wide range of chemistries offered by fluorographene chemistry open new possibilities for improving advanced energy storage devices.

Context: The potential of graphene derivatives for theranostic applications depends on their compatibility with cellular and biomolecular components. Lysophosphatidylcholine (LPC), a lipid component present in oxidized low-density lipoproteins, microvesicles and free circulation in blood, plays a critical role in the pathophysiology of various diseases. Using density functional theory-based methods, we systematically investigated the interaction of atherogenic LPC molecule with different derivatives of graphene, including pristine graphene, graphene with defect, N-doped graphene, amine-functionalized graphene, various graphene oxides and hydroxylated graphene oxides. We observed that the adsorption of LPC on graphene derivatives is highly selective based on the orientation of the functional groups of LPC interacting with the surface of the derivatives. Hydroxylated graphene oxide exhibited the strongest interaction with LPC with adsorption energy of − 2.1 eV due to the interaction between the hydroxyl group on graphene and the phosphate group of LPC. The presence of aqueous medium further enhanced this interaction indicating favourable adsorption of LPC and graphene oxide in biological systems. Such strong interaction leads to substantial change in the electronic structure of the LPC molecule, which results in the activation of this molecule. In contrast, amine-modified graphene showed the least interaction. These theoretical results are in line with our experimental fluorescence spectroscopic data of LPC/1-anilino-8-napthalene sulfonic acid complex. Our present comprehensive investigation employing both theoretical and experimental methods provides a deeper understanding of graphene-lipid interaction, which holds paramount importance in the design and fabrication of graphene-based nanomaterials for biomedical applications. Methods: In this study, we employed the density functional theory-based methods to investigate the electronic and structural properties of graphene derivatives and LPC molecule using the Quantum Espresso package. The exchange–correlation functional was described within generalized gradient approximation (GGA) as parameterized by Perdew, Burke and Ernzerhof (PBE). The valence electrons were represented using plane wave basis sets. 'The Grimme's dispersion method was used to include the van der Waals dispersion correction. [ABSTRACT FROM AUTHOR]

At present, the main raw material for producing graphene is graphite ore. However, researchers actively seek alternative resources due to their high cost and environmental problems. Biomass waste has attracted much attention due to its carbon-rich structure and renewability, emerging as a potential raw material for graphene production to be used in sports equipment. However, further progress is required on the quality of graphene produced from waste biomass. This paper, therefore, summarizes the properties, structures, and production processes of graphene and its derivatives, as well as the inherent advantages of biomass waste-derived graphene. Finally, this paper reviews graphene’s importance and application prospects in sports since this wonder material has made sports equipment available with high-strength and lightweight quality. Moreover, its outstanding thermal and electrical conductivity is exploited to prepare wearable sensors to collect more accurate sports data, thus helping to improve athletes’ training levels and competitive performance. Although the large-scale production of biomass waste-derived graphene has yet to be realized, it is expected that its application will expand to various other fields due to the associated low cost and environmental friendliness of the preparation technique.

The inherent qualities of carbon nanosheets that come from their underlying molecular structure have drawn an enormous amount of interest from researchers. Molecular descriptors are commonly used graph-theoretic metrics to analyze the physicochemical properties of a molecule based on its molecular structure. Our current research validates the use of molecular descriptors in studying three recently developed carbon allotropes: pentagraphene, phagraphene, and phographene. These allotropes have significant thermal, dynamic, and mechanical stabilities that are comparable to graphene. General analytical expressions for both degree and neighborhood degree sum-based indices of these nanosheets are derived through the utilization of graph theoretical methods. Following a filtering process of the significant indices, regression models that accurately predict atomic density, specific heat capacity and total π-electron energy of carbon allotropes are developed. Additionally, Shannon entropy is introduced as an information index, which can be utilized for predictive studies in the future and as a tool for comparing structural complexity by incorporating topological index in its definition.

There are diverse diseases such as some infections, trauma, and tumor resections during cancer surgery that can cause bone damage or skeletal defects in persons. Most of the time, these defects cannot heal spontaneously due to several medical conditions that patients encounter, like diabetes, hormone‐related problems, and autoimmune disorders. This issue is even worse for older people and some special treatments should be provided for them. Bone‐tissue engineering has emerged to tackle these challenges. By investigating bone repair strategies, studying bone structures and biomechanics, and employing appropriate growth factors, suitable scaffolds, and biomaterial‐centered regenerative approaches can be employed to treat bone defects more effectively. This study reviews some recent bone‐tissue‐engineering strategies relying on two‐dimensional (2D) materials, including graphene and its derivatives, black phosphorus, and MXenes that are exhibiting a great potential in regenerative medicine. [ABSTRACT FROM AUTHOR]

The development of new and high-performing electrode materials for sensing applications is one of the most intriguing and challenging research fields. There are several ways to approach this matter, but the use of nanostructured surfaces is among the most promising and highest performing. Graphene and graphene-related materials have contributed to spreading nanoscience across several fields in which the combination of morphological and electronic properties exploit their outstanding electrochemical properties. In this review, we discuss the use of graphene and graphene-like materials to produce gas sensors, highlighting the most relevant and new advancements in the field, with a particular focus on the interaction between the gases and the materials.

Ion and water transport at the Angstrom/Nano scale has always been one of the focuses of experimental and theoretical research. In particular, the surface properties of the angstrom channel and the solid-liquid interface interaction will play a decisive role in ion and water transport when the channel size is small to molecular or angstrom level. In this paper, the chemical structure and theoretical model of graphene oxide (GO) are reviewed. Moreover, the mechanical mechanism of water molecules and ions transport through the angstrom channel of GO are discussed, including the mechanism of intermolecular force at a solid/liquid/ion interface, the charge asymmetry effect and the dehydration effect. Angstrom channels, which are precisely constructed by two-dimensional (2D) materials such as GO, provide a new platform and idea for angstrom-scale transport. It provides an important reference for the understanding and cognition of fluid transport mechanism at angstrom-scale and its application in filtration, screening, seawater desalination, gas separation and so on. [ABSTRACT FROM AUTHOR]

Graphene, with its excellent properties and unique structure, has been extensively studied in the context of modifiable cement-based materials. However, a systematic summary of the status of numerous experimental results and applications is lacking. Therefore, this paper reviews the graphene materials that improve the properties of cement-based materials, including workability, mechanical properties, and durability. The influence of graphene material properties, mass ratio, and curing time on the mechanical properties and durability of concrete is discussed. Furthermore, graphene's applications in improving interfacial adhesion, enhancing electrical and thermal conductivity of concrete, absorbing heavy metal ions, and collecting building energy are introduced. Finally, the existing issues in current study are analyzed, and the future development trends are foreseen. [ABSTRACT FROM AUTHOR]

Allotropes of carbon are responsible for discovering the three significant carbon-based compounds, fullerene, carbon nanotubes, and graphene. Over the last few decades, groundbreaking graphene with the finest two-dimensional atomic structure has emerged as the driving force behind new research and development because of its remarkable mechanical, electrical, thermal, and optical functionalities with high surface area. Synthesis of graphene oxide (GO) and reduced graphene oxide (rGO) has resulted in numerous applications that previously had not been possible, incorporating sensing and adsorbent properties. Our study covers the most prevalent synthetic methods for making these graphene derivatives and how these methods impact the material's main features. In particular, it emphasizes the application to water purification, CO2 capture, biomedical, potential energy storage, and conversion applications. Finally, we look at the future of sustainable utilization, its applications, and the challenges which must be solved for efficient application of graphene at large scales. Graphene-based derivative implementations, obstacles, and prospects for further research and development are also examined in this review paper. [ABSTRACT FROM AUTHOR]

Graphene and its derivatives show great potential for biosensing due to their extraordinary optical, electrical and physical properties. In particular, graphene and its derivatives have excellent optical properties such as broadband and tunable absorption, fluorescence bursts, and strong polarization-related effects. Optical biosensors based on graphene and its derivatives make nondestructive detection of biomolecules possible. The focus of this paper is to review the preparation of graphene and its derivatives, as well as recent advances in optical biosensors based on graphene and its derivatives. The working principle of face plasmon resonance (SPR), surface-enhanced Raman spectroscopy (SERS), fluorescence resonance energy transfer (FRET) and colorimetric sensors are summarized, and the advantages and disadvantages of graphene and its derivatives applicable to various types of sensors are analyzed, and the methods of surface functionalization of graphene and its derivatives are introduced; these optical biosensors can be used for the detection of a range of biomolecules such as single cells, cellular secretions, proteins, nucleic acids, and antigen-antibodies; these new high-performance optical sensors are capable of detecting changes in surface structure and biomolecular interactions with the advantages of ultra-fast detection, high sensitivity, label-free, specific recognition, and the ability to respond in real-time. Problems in the current stage of application are discussed, as well as future prospects for graphene and its biosensors. Achieving the applicability, reusability and low cost of novel optical biosensors for a variety of complex environments and achieving scale-up production, which still faces serious challenges. [ABSTRACT FROM AUTHOR]

Water molecules confined in nanoscale spaces of 2D graphene layers have fascinated researchers worldwide for the past several years, especially in the context of energy storage applications. The water molecules exchanged along with ions during the electrochemical process can aid in wetting and stabilizing the layered materials resulting in an anomalous enhancement in the performance of supercapacitor electrodes. Engineering of 2D carbon electrode materials with various functionalities (oxygen (─O), fluorine (─F), nitrile (─C≡N), carboxylic (─COOH), carbonyl (─C═O), nitrogen (─N)) can alter the ion/water organization in graphene derivatives, and eventually their inherent ion storage ability. Thus, in the current study, a comparative set of functionalized graphene derivatives-fluorine-doped cyanographene (G-F-CN), cyanographene (G-CN), graphene acid (G-COOH), oxidized graphene acid (G-COOH (O)) and nitrogen superdoped graphene (G-N) is systematically evaluated toward charge storage in various aqueous-based electrolyte systems. Differences in functionalization on graphene derivatives influence the electrochemical properties, and the real-time mass exchange during the electrochemical process is monitored by electrochemical quartz crystal microbalance (EQCM). Electrogravimetric assessment revealed that oxidized 2D acid derivatives (G-COOH (O)) are shown to exhibit high ion storage performance along with maximum water transfer during the electrochemical process. The complex understanding of the processes gained during supercapacitor electrode charging in aqueous electrolytes paves the way toward the rational utilization of graphene derivatives in forefront energy storage applications., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Graphene and its derivatives have been a burning issue in the last 10 years. Although many reviews described its application in electrochemical detection, few were focused on food detection. Herein, we reviewed the recent progress in applying graphene and composite materials in food detection during the past 10 years. We pay attention to food coloring materials, pesticides, antibiotics, heavy metal ion residues, and other common hazards. The advantages of graphene composites in electrochemical detection are described in detail. The differences between electrochemical detection involving graphene and traditional inherent food detection are analyzed and compared in depth. The results proved that electrochemical food detection based on graphene composites is more beneficial. The current defects and deficiencies in graphene composite modified electrode development are discussed, and the application prospects and direction of graphene in future food detection are forecasted.

Ion and water transport at the Angstrom/Nano scale has always been one of the focuses of experimental and theoretical research. In particular, the surface properties of the angstrom channel and the solid-liquid interface interaction will play a decisive role in ion and water transport when the channel size is small to molecular or angstrom level. In this paper, the chemical structure and theoretical model of graphene oxide (GO) are reviewed. Moreover, the mechanical mechanism of water molecules and ions transport through the angstrom channel of GO are discussed, including the mechanism of intermolecular force at a solid/liquid/ion interface, the charge asymmetry effect and the dehydration effect. Angstrom channels, which are precisely constructed by two-dimensional (2D) materials such as GO, provide a new platform and idea for angstrom-scale transport. It provides an important reference for the understanding and cognition of fluid transport mechanism at angstrom-scale and its application in filtration, screening, seawater desalination, gas separation and so on.

Graphene, with its excellent properties and unique structure, has been extensively studied in the context of modifiable cement-based materials. However, a systematic summary of the status of numerous experimental results and applications is lacking. Therefore, this paper reviews the graphene materials that improve the properties of cement-based materials, including workability, mechanical properties, and durability. The influence of graphene material properties, mass ratio, and curing time on the mechanical properties and durability of concrete is discussed. Furthermore, graphene’s applications in improving interfacial adhesion, enhancing electrical and thermal conductivity of concrete, absorbing heavy metal ions, and collecting building energy are introduced. Finally, the existing issues in current study are analyzed, and the future development trends are foreseen.

Graphene-based materials have attracted much attention due to their fascinating properties such as hydrophilicity, high dispersion in aqueous media, robust size, high biocompatibility, and surface functionalization ability due to the presence of functional groups and interactions with biomolecules such as proteins and nucleic acid. Modified methods were developed for safe, direct, inexpensive, and eco-friendly synthesis. However, toxicity to the environment and animal health has been reported, raising concerns about their utilization. This review focuses primarily on the synthesis methods of graphene-based materials already developed and the unique properties that make them so interesting for different applications. Different applications are presented and discussed with particular emphasis on biological fields. Furthermore, antimicrobial potential and the factors that affect this activity are reviewed. Finally, questions related to toxicity to the environment and living organisms are revised by highlighting factors that may interfere with it. [ABSTRACT FROM AUTHOR]

Allotropes of carbon are responsible for discovering the three significant carbon-based compounds, fullerene, carbon nanotubes, and graphene. Over the last few decades, groundbreaking graphene with the finest two-dimensional atomic structure has emerged as the driving force behind new research and development because of its remarkable mechanical, electrical, thermal, and optical functionalities with high surface area. Synthesis of graphene oxide (GO) and reduced graphene oxide (rGO) has resulted in numerous applications that previously had not been possible, incorporating sensing and adsorbent properties. Our study covers the most prevalent synthetic methods for making these graphene derivatives and how these methods impact the material’s main features. In particular, it emphasizes the application to water purification, CO2 capture, biomedical, potential energy storage, and conversion applications. Finally, we look at the future of sustainable utilization, its applications, and the challenges which must be solved for efficient application of graphene at large scales. Graphene-based derivative implementations, obstacles, and prospects for further research and development are also examined in this review paper.

Abstract Understanding the underlying molecular mechanism of how graphene materials (GMs) interact with biological surfaces is the key to develop safe and effective biomedical applications of GMs. Here, a systematic and comprehensive mechanistic perspective of interactions between pristine GMs and biological membranes is provided. To this end, first the known mechanisms of interaction between GMs and membrane components are summarized and classified, with a focus on phospholipids, cholesterol, and membrane proteins. Both experimental observations and computational simulations are included. Detailed experimental conditions and physiochemical properties of GMs are listed for each cited application. At the end of this review, current challenges and conflicts that limit biomedical applications of GMs are discussed. Based on reported mechanisms, guidelines for future studies to address the remaining challenges are proposed, specifically with respect to modulating the intrinsic properties of GMs for more efficient and safer therapeutic applications.

In this work, graphene derivatives obtained by a common chemical method and a novel physical route are evaluated as reinforcement nanomaterials on prepregs based on glass fiber and epoxy resin. Besides, two types of graphite were employed to obtain graphene derivatives, through the chemical route, and to evaluate the influence of their structure quality on the performance of the composite laminates prepared. All graphene derivatives were characterized by different techniques and specific structural features were found depending on processing method; less structural damage in the graphene derivatives obtained by steam explosion and ultrasonication (physical route) was observed. Graphene derivatives were incorporated on the surface of prepregs, which were laminated to evaluate their performance through short beam tests and dynamic-mechanical analysis. Carbon materials obtained by the physical route produced remarkable thermomechanical performance, and also, better interfacial properties in the composite laminates compared to that observed with graphene oxide and reduced graphene oxide obtained from the two kinds of graphite precursor. [ABSTRACT FROM AUTHOR]

Graphene and its derivatives show great potential for biosensing due to their extraordinary optical, electrical and physical properties. In particular, graphene and its derivatives have excellent optical properties such as broadband and tunable absorption, fluorescence bursts, and strong polarization-related effects. Optical biosensors based on graphene and its derivatives make nondestructive detection of biomolecules possible. The focus of this paper is to review the preparation of graphene and its derivatives, as well as recent advances in optical biosensors based on graphene and its derivatives. The working principle of face plasmon resonance (SPR), surface-enhanced Raman spectroscopy (SERS), fluorescence resonance energy transfer (FRET) and colorimetric sensors are summarized, and the advantages and disadvantages of graphene and its derivatives applicable to various types of sensors are analyzed, and the methods of surface functionalization of graphene and its derivatives are introduced; these optical biosensors can be used for the detection of a range of biomolecules such as single cells, cellular secretions, proteins, nucleic acids, and antigen-antibodies; these new high-performance optical sensors are capable of detecting changes in surface structure and biomolecular interactions with the advantages of ultra-fast detection, high sensitivity, label-free, specific recognition, and the ability to respond in real-time. Problems in the current stage of application are discussed, as well as future prospects for graphene and its biosensors. Achieving the applicability, reusability and low cost of novel optical biosensors for a variety of complex environments and achieving scale-up production, which still faces serious challenges.

Abstract Skin is the largest organ of the human body and can perceive and respond to complex environmental stimulations. Recently, the development of electronic skin (E-skin) for the mimicry of the human sensory system has drawn great attention due to its potential applications in wearable human health monitoring and care systems, advanced robotics, artificial intelligence, and human–machine interfaces. Tactile sense is one of the most important senses of human skin that has attracted special attention. The ability to obtain unique functions using diverse assembly processible methods has rapidly advanced the use of graphene, the most celebrated two-dimensional material, in electronic tactile sensing devices. With a special emphasis on the works achieved since 2016, this review begins with the assembly and modification of graphene materials and then critically and comprehensively summarizes the most advanced material assembly methods, device construction technologies and signal characterization approaches in pressure and strain detection based on graphene and its derivative materials. This review emphasizes on: (1) the underlying working principles of these types of sensors and the unique roles and advantages of graphene materials; (2) state-of-the-art protocols recently developed for high-performance tactile sensing, including representative examples; and (3) perspectives and current challenges for graphene-based tactile sensors in E-skin applications. A summary of these cutting-edge developments intends to provide readers with a deep understanding of the future design of high-quality tactile sensing devices and paves a path for their future commercial applications in the field of E-skin.

Graphene-based materials have attracted much attention due to their fascinating properties such as hydrophilicity, high dispersion in aqueous media, robust size, high biocompatibility, and surface functionalization ability due to the presence of functional groups and interactions with biomolecules such as proteins and nucleic acid. Modified methods were developed for safe, direct, inexpensive, and eco-friendly synthesis. However, toxicity to the environment and animal health has been reported, raising concerns about their utilization. This review focuses primarily on the synthesis methods of graphene-based materials already developed and the unique properties that make them so interesting for different applications. Different applications are presented and discussed with particular emphasis on biological fields. Furthermore, antimicrobial potential and the factors that affect this activity are reviewed. Finally, questions related to toxicity to the environment and living organisms are revised by highlighting factors that may interfere with it.

Population-driven socioeconomic urban expansion, industrialization, and intensified modern agricultural practices are interlinked to environmental challenges culminating in compromised water quality due to pollution by toxic, persistent, and bioaccumulative heavy metal ions, pesticides, nitroaromatics, and other emerging pollutants. Considering the detrimental impact of pollutants on human health and ecosystem, their detection in different media including water is paramount. Notably, electrochemical techniques are more appealing owing to their recognized advantages. This research summarizes and evaluates the most recent advances in the electrochemical sensing of environmental pollutants such as heavy metal ions, pesticides, nitroaromatics, and other distinct emerging contaminants. Besides, the review focuses on the application of electrochemical detection of the selected pollutants through analysis of representative reports in the five years from 2016 to 2020. Therefore, the review is intended to contribute insights and guidelines to contemporary progress in specific electrochemical application practices based on graphene derivatives, toward the aforenamed pollutants. Thus, it focused on sensing methods such as cyclic voltammetry, anodic stripping voltammetry, and electrochemical impedance spectroscopy employing different sensing elements incorporating graphene. Moreover, the review also highlighted graphene synthesis pathways, sensor design strategies, and functionalization. Furthermore, the review showed that there is congruence in the literature that functionalized graphene and its derivatives remain as viable modifiers in electrochemical sensing of pollutants. Nonetheless, the study also appraised the absence of literature reports on electrochemical detection of natural organic matter substances like humic acid and fulvic acid using a graphene-based sensor. In reckoning, current challenges related to graphene synthesis and applicability, envisaged opportunities, and future perspectives are outlined.

GOPY is a free and open-source Python tool specifically written to automate the generation of 2D graphene-based molecular models such as pristine graphene (PG) and several graphene derivatives i.e. graphene oxide (GO), reduced graphene oxide (rGO), aminated polyethylene glycol functionalised reduced graphene oxide (rGO-PEG-NH2), and N-doped graphene (NG) in the Protein Data Bank file format (PDB). These models are generally built manually, but the process can become lengthy and cumbersome. That is especially the case when investigating larger molecules such as those used in Molecular Dynamics (MD) simulations. Using GOPY significantly speeds up the process from hours to minutes, reducing potential bias that may come with the manual placement of functional groups on a graphene layer. Moreover, the building procedure becomes effortless for the researcher, granting the possibility of producing larger and more complex molecular models than one would be able to build manually. Of its more intensive tasks, the generation of a 4 x 4 nm2 rGO-PEG-NH2 layer takes about 9 min on a CodeOcean capsule. Each model is generated in the PDB format, which is easily convertible to a wide array of other molecular formats.

Graphene derivatization to either engineer its physical and chemical properties or overcome the problem of the facile synthesis of nanographenes is a subject of significant attention in the nanomaterials research community. In this paper, we propose a facile and scalable method for the synthesis of thiolated graphene via a two-step liquid-phase treatment of graphene oxide (GO). Employing the core-level methods, the introduction of up to 5.1 at.% of thiols is indicated with the simultaneous rise of the C/O ratio to 16.8. The crumpling of the graphene layer upon thiolation without its perforation is pointed out by microscopic and Raman studies. The conductance of thiolated graphene is revealed to be driven by the Mott hopping mechanism with the sheet resistance values of 2.15 kΩ/sq and dependable on the environment. The preliminary results on the chemiresistive effect of these films upon exposure to ethanol vapors in the mix with dry and humid air are shown. Finally, the work function value and valence band structure of thiolated graphene are analyzed. Taken together, the developed method and findings of the morphology and physics of the thiolated graphene guide the further application of this derivative in energy storage, sensing devices, and smart materials.

The inherent qualities of carbon nanosheets that come from their underlying molecular structure have drawn an enormous amount of interest from researchers. Molecular descriptors are commonly used graph-theoretic metrics to analyze the physicochemical properties of a molecule based on its molecular structure. Our current research validates the use of molecular descriptors in studying three recently developed carbon allotropes: pentagraphene, phagraphene, and phographene. These allotropes have significant thermal, dynamic, and mechanical stabilities that are comparable to graphene. General analytical expressions for both degree and neighborhood degree sum-based indices of these nanosheets are derived through the utilization of graph theoretical methods. Following a filtering process of the significant indices, regression models that accurately predict atomic density, specific heat capacity and total π -electron energy of carbon allotropes are developed. Additionally, Shannon entropy is introduced as an information index, which can be utilized for predictive studies in the future and as a tool for comparing structural complexity by incorporating topological index in its definition. [ABSTRACT FROM AUTHOR]

Semiconductor-mediated photocatalysis has emerged as a sustainable technique to mitigate energy crises and environmental issues by harnessing renewable solar energy. Graphene/ MFe 2 O 4 (GSF) heterojunctions have emanated as a front runner among the visible light-responsive photocatalysts as these combine the advantages of both spinel ferrites (MFe 2 O 4) and graphene (G). Therefore, this system has been studied extensively for energy generation and environmental remediation under visible light irradiation. This review summarizes several advantageous features and modification strategies of GSF heterostructured photocatalysts in three different sections after introducing the importance of visible light photocatalysis, MFe 2 O 4 (SF) and G. Various advantages of GSF such as robust heterojunction formation, environmental benignness, improved textural properties, unique electron transport ability, facile magnetic separation efficiency and extended light absorption capability are highlighted at first. Secondly, modification techniques such as heteroatom doping and ternary composite formation have been illustrated systematically. Heteroatom doping is beneficial for decreasing the band gap energies by introducing sub-energy levels in the GSF band structure whereas ternary heterojunction construction by noble metal modification accelerates reaction kinetics and light response. GSF/semiconductor (GSF/SC) heterostructures accelerate the charge dynamics with enhanced redox ability through solid state Z-Scheme charge transfer route. Various design strategies like solvo/hydrothermal, co-precipitation, sol-gel, ball milling, etc. were briefly described with a special focus on modulation of the crystallinity, surface morphology, dimensionality and textural properties of GSF. Finally, the shortcomings in the present research as well as future research trends are addressed along with concluding remarks. [ABSTRACT FROM AUTHOR]

Microreactor technology represents one of the many methods for process intensification. Microreactors (MRs) truly inherit their tremendous properties from the dimensions of the reaction environment and their advantages cannot be overemphasized. They have remarkable heat and mass transfer rates, short molecular diffusion distance, good laminar flow, and better spatial illumination homogeneity as compared to conventional reactors due to their high surface-to-volume ratio. This review presents state-of-the-art information on the applications of this technology to photocatalytic processes involving the use of graphene (GR) derivatives, either alone or in combination with inorganic semiconductor to form nanocomposites. The latter are hybrid photocatalysts leveraging on the remarkable properties of GR, which include high electron mobility, excellent specific surface area, good mechanical and thermal properties. Because of the resulting high photonic efficiency, enhanced interfacial surface area and reduced electron-hole recombination, such catalysts are increasingly studied and tested in photocatalysis. The utilization of GR derivatives to drive advanced oxidation processes within MRs has, thus, the potential to afford a better efficiency and economic feasibility for such devices. However, studies on the application of MRs to photocatalytic processes involving the use of GR-derived semiconductors are very limited at this stage. It is hoped that this overview will serve as eye-opener for researchers, and create the needed awareness that more work is still needed to be done, in order to be able to actualize and explore the potentials of MRs. Full understanding of this technology would help in going into more details in the modelling of challenging photocatalytic reactions and in gathering enough data that can help increase photocatalytic efficiency and trigger eventual commercialization of the presented technologies. [ABSTRACT FROM AUTHOR]

This review aims to showcase the current use of graphene derivatives, graphene-based nanomaterials in particular, in biopolymer-based composites for food packaging applications. A brief introduction regarding the valuable attributes of available and emergent bioplastic materials is made so that their contributions to the packaging field can be understood. Furthermore, their drawbacks are also disclosed to highlight the benefits that graphene derivatives can bring to bio-based formulations, from physicochemical to mechanical, barrier, and functional properties as antioxidant activity or electrical conductivity. The reported improvements in biopolymer-based composites carried out by graphene derivatives in the last three years are discussed, pointing to their potential for innovative food packaging applications such as electrically conductive food packaging.

High-performance heater films are here proposed. They manifest great applicative potentiality in the de-icing technology of aircraft and motor vehicles. The films are suitable to be integrated into composite structures for the de/anti-icing function, which can be activated if the need arises. The heating is based on the joule effect of the current flowing through the electrically conductive films. Voltage and current parameters have been set based on the generators’ capacities on-board an aircraft and a car, as well as on the energy consumption during the operating conditions and the autonomy in the time. Green processes have been employed through all preparative steps of the films, which are composed of expanded graphite (60% wt/wt) and polyvinyl alcohol (PVA) (40% wt/wt). The results reveal a very significant influence of the aspect ratio of the filler on the heating and de-icing performance and suggest how to enhance the de-icing efficiency saving energy and adapting the current on-board aircraft/car generators for de-icing operations.

The aim of this paper is to prepare and characterize partially-oxidized graphite oxide and consider if it is possible to affect the level of oxidation of particles by an adjustment of the oxidizing agent. Several samples were prepared, using different amounts of oxidizing agent. The samples were subsequently analyzed. The C/O ratio was evaluated from XPS, EDS, and EA. The amount and type of individual oxygen functionalities were characterized by XPS, Raman spectroscopy, and cyclic voltammetry. The structure was studied by SEM and XRD. Thermal stability was investigated by STA-MS in argon atmosphere. The results can be useful in order to design simple technology for graphite oxide synthesis with required oxygen content.

Functionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material was used as an efficient mercury adsorbent, showing high adsorption efficiency. The adsorption isotherms were fitted using Freundlich and Langmuir models. The adsorption kinetics were fitted with pseudo-first order and pseudo-second order models. Adsorption selectivity was determined in the presence of cadmium ions and nickel ions. The presence of mentioned bivalent ions in the solution did not affect mercury adsorption efficiency.

In general, alumina membranes have been extensively developed for protein separation and purification. Alumina membranes, which naturally feature a moderate hydrophilic character (contact angle of 40–50°) and the lowest cost among other oxide materials, are most suitable for these applications. Membrane fouling occurs due to the deposition and adsorption of proteins on the surface and pore walls of alumina membranes. This is one of the major issues that prevent the applicability of alumina membranes. Therefore, it is important to minimise membrane fouling by enhancing the hydrophilic character of the membranes as well as reducing interactions between proteins and the membranes surface. This review discusses the surface modification of alumina membranes in an effort to enhance the hydrophilic character of the membranes. Moreover, the introduction of graphene derivatives in modifying the hydrophilicity of alumina is also addressed. The superhydrophilic character of the alumina surface has a major influence on its anti-fouling and permeate flux properties, thus it improves the performance of the protein separation and purification processes. [ABSTRACT FROM AUTHOR]

Graphene is highly efficient in reinforcing metal matrix composites due to its intrinsic ultrahigh mechanical properties. Several synthesis methods have been developed to produce graphene. Consequently, the selection of graphene materials with various structures, such as layer number, lateral dimension and chemical modification, is a key issue to synthesize graphene-related composites. In the present study, two kinds of graphene derivatives, namely graphene nanoplatelets (GNPs) and reduced graphene oxide (RGO), were adopted to fabricate copper matrix composites through a modified molecular-level mixing process. Microstructure studies showed that GNPs exhibited flake shape, and RGO exhibited irregular strip or sheet shape in the composites powders. Some spherical-shape nanosized GNPs or RGO dispersed within Cu grain interiors were also observed under the transmission electron microscope. Both of the GNPs and RGO were well bonded with the copper matrix after sintering. GNPs showed an obvious aggregative trend when the volume fraction was above 0.5%, but 1.0 vol.% RGO was still uniformly dispersed in the matrix. Tensile tests indicated that GNPs showed good strengthening efficiency at content below 0.5 vol.% while RGO performed better when the content increased from 0.5 to 1.0 vol.%. The difference of relevant strengthening effect and mechanisms involved in the two composites were systematically discussed by combining with theory consideration and experimentation. [ABSTRACT FROM AUTHOR]