Graphene-based Nanocomposites Research Articles

Bioinspired Reduced Graphene Oxide Based Nanohybrids for Photocatalysis and Antibacterial Applications.

Ultra-thin graphene has been receiving significance in the diverse sections of material science, owing to its exceptional physicochemical and thermo-mechanical characteristics. Currently, the fabrication of high-grade graphene in an economical target and green procedures area is a massive concern. Among the diverse techniques, chemical-mediated fabrication is believed to be the finest process since it is simple, scalable, and of low-cost; however, it involves noxious or hazardous chemical reducers for producing functional graphene-based Nanocomposites (NCs). Therefore, around the globe, scientists are endeavoring to adopt the bioinspired techniques to manufacture the functional reduced Graphene Oxide (rGO) and reduced Graphene Oxide-Metal/Metal Oxide (rGO-M/MO) NCs. Hence, keeping this issue in mind, the present review article summarize and integrates the current state of knowledge about the diverse bioinspired strategies developed to obtain rGO and rGO-M/MO NCs and their photocatalytic, antibacterial, and cytotoxic assessments.

The Effect of Graphene Oxide Dispersion on Structure-Property Relationships in Graphene-Based Polymer Nanocomposites

The performance of graphene/polymer nanocomposites depends on many factors but the major factor is a nanoparticles dispersion and distribution into the host matrix. The present work investigates the effect of the dispersion of graphene oxide upon the structure-property relations in metallocene linear low density polyethylene (PE), homo polypropylene (PP), and blends thereof. These nanocomposites were prepared by solvent processing, where DMF and o-xylene were used as solvents for Graphene Oxide (GO) powder and the polymers respectively, before the two components were combined to form a well-mixed initial state. Characterization of the structure and crystallization of the nanocomposites was carried out by small- and wide-angle X-ray scattering and diffraction (SAXS and WAXD). The chemical structures were characterized by Fourier transform infrared spectroscopy (FTIR) and by Raman spectroscopy, and the latter used to calculate the ID/IG value for a pure GO samples. The thermal properties of the resulting nanocomposites were investigated by DSC and TGA in order to obtain Melting temperature ( ), crystallization temperature ( ) and degree of crystallinity ( ) as well as a range of degradation temperatures. The effect of GO on the mechanical properties was studied via the ultimate tensile strength and elastic modulus.

Bio-Inspired Facile Synthesis of Graphene-Based Nanocomposites: Elucidation of Antimicrobial and Biofilm Inhibitory Potential against Foodborne Pathogenic Bacteria

Herein, a new and simple biogenic method for the preparation of gold nanoparticles (AuNPs) and their reduced graphene oxide based nanocomposites (Au-RGO) by using microwave irradiation method for antimicrobial and biofilm inhibition against foodborne pathogenic bacteria was reported. X-ray diffraction (XRD), Raman, and transmission electron microscopy (TEM) analyses confirmed that the AuNPs with face centered cubic (FCC) structure were indeed anchored onto the RGO sheets. Ultraviolet-Vis (UV-VIS) spectrum showed a shifting and broadening of absorption peaks of AuNPs when attached on the surface of RGO sheets. The effect of sub-inhibitory concentrations of Au-RGO nanocomposites on biofilm formation in five foodborne pathogens was assessed. Au-RGO nanocomposites reduced the formation of biofilm by 75%, 78%, 68%, 80% and 79% in L. monocytogenes, MRSA, E. coli, S. marcescens and P. aeruginosa, respectively. Exopolysaccharides (EPS), a vital component of the biofilm was also inhibited significantly and pre-formed mature biofilms were also reduced considerably. Further, this study demonstrated that the reactive oxygen species (ROS) generation induced in bacterial cells as a result of Au-RGO treatment could be the plausible mechanism for biofilm inhibitory action. The tested concentrations were found non-toxic to human embryonic kidney cell lines (HEK-293). The investigation highlights the broad-spectrum biofilm inhibitory properties of Au-RGO nanocomposites that could be exploited in the food industry to prevent biofilm-based food contamination.

Graphene and Perovskite-Based Nanocomposite for Both Electrochemical and Gas Sensor Applications: An Overview.

Perovskite and graphene-based nanocomposites have attracted much attention and been proven as promising candidates for both gas (H2S and NH3) and electrochemical (H2O2, CH3OH and glucose) sensor applications. In this review, the development of portable sensor devices on the sensitivity, selectivity, cost effectiveness, and electrode stability of chemical and electrochemical applications is summarized. The authors are mainly focused on the common analytes in gas sensors such as hydrogen sulfide, ammonia, and electrochemical sensors including non-enzymatic glucose, hydrazine, dopamine, and hydrogen peroxide. Finally, the article also addressed the stability of composite performance and outlined recent strategies for future sensor perspectives.

Hydrogen Storage on Nanoporous Carbon Foam for Electrochemical Applications

To be able to mitigate the threat of climate change, we need an alternative to fossil fuels. The use of hydrogen in fuel cells is an ideal candidate because hydrogen can be produced in many different ways and has a high energy density. However, one challenge in using hydrogen as a fuel is its storage. Storing hydrogen as compressed gas typically requires large pressures to meet US Department of Energy (DOE) targets, which leads to large losses during compression. By using solid state storage, we can use lower pressures for storage. Of the different kinds of solid state storage, physisorption on carbon materials has great potential because of its fast kinetics, reversibility, and the cost effectiveness of carbon materials.In this research, we investigate the storage of hydrogen gas through physical adsorption on a sodium ethoxide-derived carbon foam. This carbon foam has all the necessary requirements of a good hydrogen sorbent: very large surface area and a large micropore volume. This material is also easy to synthesize: sodium ethoxide is pyrolyzed in N2 to make carbon, which is then washed in DI water and vacuum filtered. Unlike many other high surface area carbon materials, this carbon foam does not require a two-step carbonization-activation process, nor does it require a sacrificial template. This means it is more scalable and energy efficient compared to other synthetic carbon materials. [1,2]The hydrogen adsorption capability of this material is tested at both 77K and 298K at elevated pressures (up to 9.5 MPa). Both the excess hydrogen uptake and the total hydrogen uptake are discussed. The values obtained are comparable with benchmark materials such as MOF-5 and IRMOF-20, which have 8 wt% and 10 wt% total uptake at 10 MPa, respectively, [3] and could plausibly meet US DOE targets for light duty vehicle application (5.5 wt% total uptake) at a much lower pressure than conventional compressed gas storage (usually 70 MPa). This work shows the potential of nanoporous carbon materials such as ours to work as a new storage system or as a ‘range extender’ of sorts for existing fuel cell vehicles.[1] Lyth, S. M., Shao, H., Liu, J., Sasaki, K., and Akiba, E., 2014, “Hydrogen Adsorption on Graphene Foam Synthesized by Combustion of Sodium Ethoxide,” Int. J. Hydrogen Energy, 39(1), pp. 376–380.[2] Choucair, M., and Mauron, P., 2015, “Versatile Preparation of Graphene-Based Nanocomposites and Their Hydrogen Adsorption,” Int. J. Hydrogen Energy, 40(18), pp. 6158–6164.[3] Ahmed, A., Seth, S., Purewal, J., Wong-Foy, A. G., Veenstra, M., Matzger, A. J., and Siegel, D. J., 2019, “Exceptional Hydrogen Storage Achieved by Screening Nearly Half a Million Metal-Organic Frameworks,” Nat. Commun., 10(1), pp. 1–9.

Magnetic graphene-based nanocomposites as highly efficient absorbents for Cr(VI) removal from wastewater.

Due to the merits of their high adsorption and convenient separation, magnetic graphene-based composites have become a promising adsorbent in terms of wastewater treatment. However, recycling and regeneration properties of magnetic graphene-based composites are still a conundrum, which remains to be resolved. Here, Fe3O4/reduced graphene oxide (RGO) (Fe3O4/RGO) nanocomposites were synthesized by one-step solvent-thermal reduction route and used as adsorbents for water purification. It was encouraging to find that the nanocomposites possessed many intriguing properties in removing of Cr(VI) ions, including high adsorption efficiency and excellent recycling and regeneration property. The results indicated that the magnetic separation process of the Fe3O4/RGO nanocomposites only took less than 5s and the maximum removal efficiency of Cr(VI) reached 99.9% under the optimum experimental conditions. Most significantly, the adsorption rate of Cr(VI) can still be as high as 98.13% after 10cycles and the single recycle quality of the nanocomposites can maintain at more than 80%. As a result, the Fe3O4/RGO nanocomposites could be a potential adsorbent for removing heavy metal ions effectively, especially in environmental protection and restoration.

An Overview on Graphene-Metal Oxide Semiconductor Nanocomposite: A Promising Platform for Visible Light Photocatalytic Activity for the Treatment of Various Pollutants in Aqueous Medium.

Graphene is one of the most favorite materials for materials science research owing to its distinctive chemical and physical properties, such as superior conductivity, extremely larger specific surface area, and good mechanical/chemical stability with the flexible monolayer structure. Graphene is considered as a supreme matrix and electron arbitrator of semiconductor nanoparticles for environmental pollution remediation. The present review looks at the recent progress on the graphene-based metal oxide and ternary composites for photocatalysis application, especially for the application of the environmental remediation. The challenges and perspectives of emerging graphene-based metal oxide nanocomposites for photocatalysis are also discussed.

New Design of Active Material Based on YInWO4-G-SiO2 for a Urea Sensor and High Performance for Nonenzymatic Electrical Sensitivity.

In the present study, electrochemical sensing for urea was proposed utilizing graphene-based quaternary nanocomposites YInWO4-G-SiO2 (YIWGS). These YIWGS nanocomposites were utilized due to their exceptionally delicate determination of urea with the lowest detection limit (0.01 mM). These YIWGS composites were developed through a simple self-assembly method. From physical characterization, we found that the YIWGS composites are crystalline in nature (powdered X-ray diffraction), and Fourier transform infrared (FTIR) spectroscopy analysis provided the surface functionality and bonding. Scanning electron microscopy (SEM) studies indicated the morphology characteristics of the as-synthesized composites and the high-resolution transmission electron microscopy (HRTEM) image supported the formation of cubic or hexagonal morphology of the YIW nanocomposites. The YIWGS sensor showed a great electroanalytical sensing performance of 0.07 mM urea with a sensitivity of 0.06 mA cm-2, an expansive linear range of 0.7-1.5 mM with a linear response (R2 1/4 0.99), and an eminent reaction time of around 2 s. It also displayed a good linear response toward urea with negligible interferences from normal coinciding species in urine samples.

A Review on the Development of Non-Enzymatic Glucose Sensor Based on Graphene-Based Nanocomposites

In this 21th century, the demand for glucose sensors in monitoring diabetes reaches a year-on-year peak due to the unhealthy lifestyle of society. Therefore, it is the utmost important task for scientists and researchers to develop a highly efficient and effective glucose sensor. However, conventional enzymatic glucose sensors have showed some drawbacks and the underlying issues faced by enzymatic glucose sensors are outlined in this paper. With the tremendous advancement of science and technology, the field of diabetes monitoring has evolved from enzymatic to nonenzymatic glucose sensor that heavily emphasized on the usage of nanomaterial. This transformation is supported by various justifications such as a better stability of nonenzymatic sensors towards the surrounding, higher sensitivity and ease of fabrication. Numerous materials including graphene, noble metals, (transition) metal oxides and composites have been explored for its potential in the development and performance improvement of nonenzymatic glucose sensors. This paper reviewed nonenzymatic glucose sensors, their mechanism of glucose oxidation and various promising graphene-based nanocomposite systems as well as the challenges and future perspectives of glucose biosensors.

Urethane-Acrylate/Aramid Nanocomposites Based on Graphenic Materials. A Comparative Study of Their Mechanical Properties

Urethane-acrylate thermoset resins (UATR) are a new type of polymeric matrix that have recently made a strong breakthrough in the composites sector. This is because of their properties, which make them an advantageous alternative to epoxy resins, especially if they are reinforced with high-performance fibers such as aramids. Graphene-based nanocomposites are one of the most dynamic research fields in nanotechnology, because graphenic materials greatly improve the properties of traditional composites. This work represents a comparative study of the effect of adding three types of graphenic materials on the mechanical properties of UATR/aramid composites. Several UATR polymeric matrices were doped at 2% w/w with graphene nanoplatelets (GNPs), reduced graphene oxide (rGO) and pristine few-layer graphene (FLG), and reinforced with Twaron CT709 para-aramid fibers. The obtained laminates showed low density (1.38 g·cm−3), a high volumetric fiber–resin ratio (80:20), homogeneous dispersion of the nanoreinforcement, high reproducibility, and easy scalability. The tensile, flexural and impact strength properties of the undoped composite and the graphene-doped nanocomposites were determined. FLG-doped nanocomposites showed the highest increase in all the mentioned mechanical properties and attained a very significant relative improvement over the undoped laminate (up to 134.4% in aCU).

Current Research of Graphene-Based Nanocomposites and Their Application for Supercapacitors.

This review acmes the latest developments of composites of metal oxides/sulfide comprising of graphene and its analogues as electrode materials in the construction of the next generation of supercapacitors (SCs). SCs have become an indispensable device of energy-storage modes. A prompt increase in the number of scientific accomplishments in this field, including publications, patents, and device fabrication, has evidenced the immense attention they have attracted from scientific communities. These efforts have resulted in rapid advancements in the field of SCs, focusing on the development of electrode materials with features of high performance, economic viability, and robustness. It has been demonstrated that carbon-based electrode materials mixed with metal oxides and sulfoxides can perform extremely well in terms of energy density, durability, and exceptional cyclic stability. Herein, the state-of-the-art technologies relevant to the fabrication, characterization, and property assessment of graphene-based SCs are discussed in detail, especially for the composite forms when mixing with metal sulfide, metal oxides, metal foams, and nanohybrids. Effective synthetic methodologies for the nanocomposite fabrications via intercalation, coating, wrapping, and covalent interactions will be reviewed. We will first introduce some fundamental aspects of SCs, and briefly highlight the impact of graphene-based nanostructures on the basic principle of SCs, and then the recent progress in graphene-based electrodes, electrolytes, and all-solid-state SCs will be covered. The important surface properties of the metal oxides/sulfides electrode materials (nickel oxide, nickel sulfide, molybdenum oxide, ruthenium oxides, stannous oxide, nickel-cobalt sulfide manganese oxides, multiferroic materials like BaMnF, core-shell materials, etc.) will be described in each section as per requirement. Finally, we will show that composites of graphene-based electrodes are promising for the construction of the next generation of high performance, robust SCs that hold the prospects for practical applications.

Antibacterial properties of starch-reduced graphene oxide–polyiodide nanocomposite

Graphene-based nanocomposites with superior antibacterial activity are highly sought after by the food packaging industries. Here, we report for the first time a method that utilizes soluble starch biopolymer as a functionalizing and reducing agent for the preparation of starch-reduced graphene oxide (SRGO), whereby polyiodide binds to the helical structures of amylose units of the starch (chromophore) to form a SRGO–polyiodide nanocomposite (SRGO–PI NC). UV–visible spectroscopy, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy confirmed the presence of polyiodide in SRGO. SRGO–PI NC exhibited good antibacterial activities against pathogenic Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) microbes with minimum inhibitory concentrations (MICs) and minimum bactericidal concentration (MBC) values (as determined by a broth-dilution method) of 2.5 and 5 mg/ml, respectively, for both E. coli and S. aureus. PrestoBlue viability assays showed half-maximal inhibitory concentration (IC50) values of 0.45 and 0.41 mg/ml for E. coli and S. aureus, respectively. Time-kill kinetic and live/dead bacterial viability assays revealed the antimicrobial activities of SRGO-PI NC against both E. coli and S. aureus. The study provides new insights regarding the utilization of graphene–polyiodide NCs as high-efficacy antibacterial starch-based nanomaterials for food packaging applications.

Thermal and morphological study of graphene based polyurethane composites

Graphene-based polymer nanocomposites are highly used in the field of membranes, biomedical aids, automotive, electronics, actuators, aerospace and sensors. In this paper, the thermal and morphological study of polyurethane nanocomposites was carried out. Polyurethane nanocomposites were fabricated using the melt mixing in the presence of a solvent. Different weight percentages of graphene (2.5 wt%, 5 wt%, and 10 wt%) were incorporated for preparing the nanocomposites. The morphological study of the polyurethane and nanocomposites samples was explored by scanning electron microscope (SEM) to observe the dispersion of graphene nanomaterials in the polyurethane matrix. Fourier Transform Infrared Spectroscopy (FTIR) was applied to examine the chemical properties of the different polyurethane nanocomposite. The existence of graphene in the polyurethane matrix was studied using X-ray diffraction (XRD). The thermal analysis of the nanocomposite samples was analyzed using Thermogravimetric analysis (TGA). SEM showed that the graphene is dispersed throughout the polyurethane matrix. FTIR investigation showed that there is no change in the chemical properties of the polyurethane with the addition of graphene. XRD technique confirms the existence of graphene in the polyurethane matrix. TGA analysis concluded that the integration of graphene in the polyurethane matrix increases the thermal stability property of polyurethane. Therefore, as a result of the current study, polyurethane nanocomposites can be fabricated without any changes in chemical properties.

Mechano-adaptive thin film of graphene-based polymeric nanocomposite for enhancement of lubrication properties

Intriguing low frictional properties of 2D materials can be harnessed for thin-film lubrication in small-scale devices by making their mechano-adaptive coatings. Herein, the reduced graphene oxide-polystyrene (rGO-PS) nanocomposite synthesized by single-step chemical processing of graphene oxide and polystyrene is applied to prepare self-lubricating thin film over the silicon substrate. The non-covalent π-π interaction between the aromatic rings of polystyrene and the π-electron network of rGO furnished excellent interfacial adhesion and extended the mechanical strengthening and lubrication properties. The interfacial interaction is further supported by higher glass transition and thermal decomposition temperatures of the rGO-PS nanocomposite. The rGO-PS thin film with a uniform thickness of 850 nm is coated on a silicon surface by a spray pyrolysis deposition technique. The rGO-PS thin film showed significantly low friction (μ = 0.12) compared to the silicon substrate (μ = 0.6). The microscopic and spectroscopic analyses confirmed the deposition of a graphene-based thin film on the counter interface of the steel ball. Furthermore, the rGO-PS thin film couldn’t damage/rupture even after 100,000 cyclic contacts, which revealed its remarkable wear-resistivity. The excellent mechano-adaptability and low frictional properties of rGO-PS thin film promise the potential of 2D nanomaterials for thin-film lubrication applications.

Tuning plasmonic nanostructures in graphene-based nano-sandwiches using ultraviolet/ozone functionalization

Graphene-based plasmonic sandwiches have received considerable research interest because of their intriguing optical, electronic and catalytic properties. The capability of tuning the distribution of plasmonic nanostructures is essential for exploring their intrinsic properties and potential applications. Herein, we report an ultraviolet (UV)/ozone-assisted approach to synthesizing gold nanoparticles/reduced graphene oxide/gold thin film (AuNPs/RGO/Au) plasmonic nano-sandwiches with easy and fine tunability of AuNPs at room temperature. The UV/ozone functionalization controls the activation of anchor sites for AuNPs on the GO scaffold without creating new defects on the basal plane. By simply varying the functionalization time, the loading density of AuNPs with an average size of ~ 17 nm is able to reach a value of over 500 μm−2, which is higher than previously reported values using other room-temperature methods. The AuNPs/RGO/Au plasmonic nano-sandwiches offer remarkable near-field enhancement with an enhancement factor of over 300 in the Raman signal of graphene, which is comparable with the highest reported values. The as-prepared AuNPs/RGO/Au nano-sandwiches can be used as sensitive surface-enhanced Raman spectroscopy substrates. This work demonstrates that oxygen-containing functional groups, which were commonly considered to have negative effects on graphene-based nanocomposites, can contribute to the successful synthesis of high-loading plasmonic nano-sandwiches.

Synthesis of gold and palladium nanoparticles supported on CuO/rGO using imidazolium ionic liquid for CO oxidation

A simple ionic liquid-assisted approach for the fabrication of graphene-based nanocomposite is reported. Pd–CuO/rGO and Au–CuO/rGO nanocomposites are successfully fabricated with the assistance of the ionic liquid 1-butyl-3-methyl imidazolium tetrafluoroborate. The physicochemical features of nanocomposite are systematically characterized by XRD, FT-IR, Raman spectroscopy, XPS, TGA, FESEM, AFM, and HRTEM. Carbon monoxide has been used as a probe molecule to emphasize the performance of the fabricated materials. The results indicate that the incorporation of a little quantity of ionic liquid results in the creation of uniformly dispersed NPs simultaneously with the reduction of graphene oxide (GO) into rGO, which leads to a low-temperature CO oxidation process. Besides, the Au–CuO/rGO catalyst achieved excellent durability in CO oxidation for 14 h, without detectable deactivation. The low-temperature CO oxidation was mainly induced by the synergistic effects between the components of catalysts. The Au or Pd and CuO combination not only generates more interfaces, which is more favorable for the activation of oxygen but also enhances the catalyst reduction behavior. Consequently, a graphene composite catalyst can be considered a potential CO oxidation candidate.

Anti-corrosion reinforcement of waterborne polyurethane coating with polymerized graphene oxide by the one-pot method

The research and preparation of excellent anti-corrosion coatings is still a difficult task and critical to practical applications. In this paper, phosphoric acid, dodecylbenzenesulfonic acid (DBSA), and polyaniline (PANI) were polymerized in-situ onto graphene oxide (GO) by the one-pot method to prepare dodecylbenzenesulfonic acid-PANI/phosphorylated graphene oxide (DPPGO). The results of TEM, FTIR, Raman spectrum, XRD, TGA, and XPS analysis showed that the DPPGO was successfully prepared. The SEM observations showed that DPPGO has best dispersibility and compatibility than GO and PANI/phosphorylated graphene oxide (PPGO) in waterborne polyurethane (WPU) matrix. To achieve anti-corrosion performance, a new type of graphene-based polymer nanocomposites water-based coating was developed and tested by electrochemical measurements. Through a series of electrochemical tests, it is concluded that the anti-corrosion performance of a composite coating DPPGO is significantly improved. The excellent anti-corrosion properties are due to the perfect dispersion and good compatibility of DPPGO in WPU.

Graphene-family materials in electrochemical aptasensors.

The study of graphene-based carbon nanocomposites has remarkably increased in recent years. Functionalized graphene-based nanostructures, including graphene oxide and reduced graphene oxide, have great potential as new innovative electrode materials in the fabrication of novel electrochemical sensors. Electrochemical sensors based on aptamers attracted great attention because of their high sensitivity and selectivity, and simple instrumentation, as well as low production cost. Aptamers as a potent alternative to antibodies are functional nucleic acids with a high tendency to specific analytes. Electrochemical aptasensors show specific recognition ability for a wide range of analytes. Although aptamers are selected in vitro in contrast to antibodies, they are interesting due to advantages like high stability, easy chemical modifications, and the potential to be employed in nanostructured device fabrication or electrochemical sensing devices. Recently, new nanomaterials have shown a significant impact on the production of electrochemical sensors with high efficiency and performance. This review aims to give an outline of electrochemical aptasensors based on the graphene family materials and discuss the detection mechanism in this type of aptasensors. The present review summarizes some of the recent achievements in graphene-based aptasensors and includes their recent electroanalytical applications. Graphical Abstract Graphical Abstract.

Micro-scale computational modeling of graphene-based nanocomposites – Influence of filler-matrix interface failure

The effect of failure at the filler-matrix interface on the tensile stress-strain response of graphene-based polymer nanocomposites is studied using micro-scale finite element (FE) modeling. Interfacial failure can occur in the form of debonding or slip. Based on previous studies (Jiang et al., 2014; Anagnostopoulos et al., 2015; Li et al., 2017), interfacial slip, which causes friction-like interaction between the filler and matrix, is identified as the major failure mechanism that affects the nanocomposite response. By establishing single-filler models in ABAQUS, it is demonstrated that interfacial slip affects the stress-strain response of the nanocomposite in two ways. Firstly, it limits the load that can be transferred to the filler. Secondly, it causes a shear displacement discontinuity across the interface, and this generates additional strain over and above those of the matrix and filler; this reduces the level of stress enhancement in the nanocomposite that the incorporation of fillers contribute, and under certain conditions, even weaken the nanocomposite. Models with fully aligned and randomly oriented fillers are also established to examine the influence of parameters such as filler orientation, interfacial slip strength, and filler aspect ratio, on the tensile response of the nanocomposite. The model developed is employed to describe the tensile response of an actual polyvinyl alcohol (PVA)- graphene oxide (GO) nanocomposite, and good correlation with experiments is observed.

Effect of Pt nanoparticle decoration on the H2 storage performance of plasma-derived nanoporous graphene

A nanoporous and large surface area (∼800 m2/g) graphene-based material was produced by plasma treatment of natural flake graphite and was subsequently surface decorated with platinum (Pt) nano-sized particles via thermal reduction of a Pt precursor (chloroplatinic acid). The carbon-metal nanocomposite showed a ∼2 wt% loading of well-dispersed Pt nanoparticles (<2 nm) across its porous graphene surface, while neither a significant surface chemistry alteration nor a pore structure degradation was observed due to the Pt decoration procedure. The presence of Pt seems to slightly promote the hydrogen sorption behavior at room temperature with respect to the pure graphene, thus implying the rise of “weak” chemisorption phenomena, including a potential hydrogen “spillover” effect. The findings of this experimental study provide insights for the development of novel graphene-based nanocomposites for hydrogen storage applications at ambient conditions.