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Journal articles on the topic 'Graphene'
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1
Cao, Qiang, Xiao Geng, Huaipeng Wang, Pengjie Wang, Aaron Liu, Yucheng Lan, and Qing Peng. "A Review of Current Development of Graphene Mechanics." Crystals 8, no. 9 (September 6, 2018): 357. http://dx.doi.org/10.3390/cryst8090357.
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Graphene, a two-dimensional carbon in honeycomb crystal with single-atom thickness, possesses extraordinary properties and fascinating applications. Graphene mechanics is very important, as it relates to the integrity and various nanomechanical behaviors including flexing, moving, rotating, vibrating, and even twisting of graphene. The relationship between the strain and stress plays an essential role in graphene mechanics. Strain can dramatically influence the electronic and optical properties, and could be utilized to engineering those properties. Furthermore, graphene with specific kinds of defects exhibit mechanical enhancements and thus the electronic enhancements. In this short review, we focus on the current development of graphene mechanics, including tension and compression, fracture, shearing, bending, friction, and dynamics properties of graphene from both experiments and numerical simulations. We also touch graphene derivatives, including graphane, graphone, graphyne, fluorographene, and graphene oxide, which carve some fancy mechanical properties out from graphene. Our review summarizes the current achievements of graphene mechanics, and then shows the future prospects.
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Inagaki, Michio, and Feiyu Kang. "Graphene derivatives: graphane, fluorographene, graphene oxide, graphyne and graphdiyne." J. Mater. Chem. A 2, no. 33 (2014): 13193–206. http://dx.doi.org/10.1039/c4ta01183j.
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Kumar, Kamal, Nora H. de Leeuw, Jost Adam, and Abhishek Kumar Mishra. "Strain-induced bandgap engineering in 2D ψ-graphene materials: a first-principles study." Beilstein Journal of Nanotechnology 15 (November 20, 2024): 1440–52. http://dx.doi.org/10.3762/bjnano.15.116.
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High mechanical strength, excellent thermal and electrical conductivity, and tunable properties make two-dimensional (2D) materials attractive for various applications. However, the metallic nature of these materials restricts their applications in specific domains. Strain engineering is a versatile technique to tailor the distribution of energy levels, including bandgap opening between the energy bands. ψ-Graphene is a newly predicted 2D nanosheet of carbon atoms arranged in 5,6,7-membered rings. The half and fully hydrogenated (hydrogen-functionalized) forms of ψ-graphene are called ψ-graphone and ψ-graphane. Like ψ-graphene, ψ-graphone has a zero bandgap, but ψ-graphane is a wide-bandgap semiconductor. In this study, we have applied in-plane and out-of-plane biaxial strain on pristine and hydrogenated ψ-graphene. We have obtained a bandgap opening (200 meV) in ψ-graphene at 14% in-plane strain, while ψ-graphone loses its zero-bandgap nature at very low values of applied strain (both +1% and −1%). In contrast, fully hydrogenated ψ-graphene remains unchanged under the influence of mechanical strain, preserving its initial characteristic of having a direct bandgap. This behavior offers opportunities for these materials in various vital applications in photodetectors, solar cells, LEDs, pressure and strain sensors, energy storage, and quantum computing. The mechanical strain tolerance of pristine and fully hydrogenated ψ-graphene is observed to be −17% to +17%, while for ψ-graphone, it lies within the strain span of −16% to +16%.
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Banerjee, Arghya Narayan. "Graphene and its derivatives as biomedical materials: future prospects and challenges." Interface Focus 8, no. 3 (April 20, 2018): 20170056. http://dx.doi.org/10.1098/rsfs.2017.0056.
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Graphene and its derivatives possess some intriguing properties, which generates tremendous interests in various fields, including biomedicine. The biomedical applications of graphene-based nanomaterials have attracted great interests over the last decade, and several groups have started working on this field around the globe. Because of the excellent biocompatibility, solubility and selectivity, graphene and its derivatives have shown great potential as biosensing and bio-imaging materials. Also, due to some unique physico-chemical properties of graphene and its derivatives, such as large surface area, high purity, good bio-functionalizability, easy solubility, high drug loading capacity, capability of easy cell membrane penetration, etc., graphene-based nanomaterials become promising candidates for bio-delivery carriers. Besides, graphene and its derivatives have also shown interesting applications in the fields of cell-culture, cell-growth and tissue engineering. In this article, a comprehensive review on the applications of graphene and its derivatives as biomedical materials has been presented. The unique properties of graphene and its derivatives (such as graphene oxide, reduced graphene oxide, graphane, graphone, graphyne, graphdiyne, fluorographene and their doped versions) have been discussed, followed by discussions on the recent efforts on the applications of graphene and its derivatives in biosensing, bio-imaging, drug delivery and therapy, cell culture, tissue engineering and cell growth. Also, the challenges involved in the use of graphene and its derivatives as biomedical materials are discussed briefly, followed by the future perspectives of the use of graphene-based nanomaterials in bio-applications. The review will provide an outlook to the applications of graphene and its derivatives, and may open up new horizons to inspire broader interests across various disciplines.
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Dolina, Ekaterina S., Pavel A. Kulyamin, Anastasiya A. Grekova, Alexey I. Kochaev, Mikhail M. Maslov, and Konstantin P. Katin. "Thermal Stability and Vibrational Properties of the 6,6,12-Graphyne-Based Isolated Molecules and Two-Dimensional Crystal." Materials 16, no. 5 (February 27, 2023): 1964. http://dx.doi.org/10.3390/ma16051964.
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We report the geometry, kinetic energy, and some optical properties of the 6,6,12-graphyne-based systems. We obtained the values of their binding energies and structural characteristics such as bond lengths and valence angles. Moreover, using nonorthogonal tight-binding molecular dynamics, we carried out a comparative analysis of the thermal stability of 6,6,12-graphyne-based isolated fragments (oligomer) and two-dimensional crystals constructed on its basis in a wide temperature range from 2500 to 4000 K. We found the temperature dependence of the lifetime for the finite graphyne-based oligomer as well as for the 6,6,12-graphyne crystal using a numerical experiment. From these temperature dependencies, we obtained the activation energies and frequency factors in the Arrhenius equation that determine the thermal stability of the considered systems. The calculated activation energies are fairly high: 1.64 eV for the 6,6,12-graphyne-based oligomer and 2.79 eV for the crystal. It was confirmed that the thermal stability of the 6,6,12-graphyne crystal concedes only to traditional graphene. At the same time, it is more stable than graphene derivatives such as graphane and graphone. In addition, we present data on the Raman and IR spectra of the 6,6,12-graphyne, which will help distinguish it from the other carbon low-dimensional allotropes in the experiment.
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Wu, Li Li, Xiang Lv, and Chao Can Zhang. "Preparation and Dispersion of Polyacrylamide-Grafting Graphene." Advanced Materials Research 306-307 (August 2011): 1360–63. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.1360.
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Graphene has weak interface compatibility to its solvent, and it is easy to get agglomeration in the solvent. In this paper, graphehe is modified by grafting method to improve the aqueous dispersion. Oxidized graphene is firstly prepared by modified Hummer’s method and supersonic exfoliation. Then oxidized graphene is grafted by hydrophilic polymer polyacrylamide (PAM) and deoxidized into modified graphene. The product is characterized by TEM, FTIR, Raman spectroscopy and sedimentation test. And the result demonstrates a modified graphene is successfully synthesized and its compatibility to the media is enhanced as assumption. When the ratio between PAM and graphene is 1:10, the suspension absorbance is improved as twice as common graphene’s. Meanwhile the concentration of graphene in suspension can reach 0.05mg/ml without any agglomeration.
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Woellner, Cristiano Francisco, Pedro Alves da Silva Autreto, and Douglas S. Galvao. "One Side-Graphene Hydrogenation (Graphone): Substrate Effects." MRS Advances 1, no. 20 (2016): 1429–34. http://dx.doi.org/10.1557/adv.2016.196.
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ABSTRACTRecent studies on graphene hydrogenation processes showed that hydrogenation occurs via island growing domains, however how the substrate can affect the hydrogenation dynamics and/or pattern formation has not been yet properly investigated. In this work we have addressed these issues through fully atomistic reactive molecular dynamics simulations. We investigated the structural and dynamical aspects of the hydrogenation of graphene membranes (one-side hydrogenation, the so called graphone structure) on different substrates (graphene, few-layers graphene, graphite and platinum). Our results also show that the observed hydrogenation rates are very sensitive to the substrate type. For all investigated cases, the largest fraction of hydrogenated carbon atoms was for platinum substrates. Our results also show that a significant number of randomly distributed H clusters are formed during the early stages of the hydrogenation process, regardless of the type of substrate. These results suggest that, similarly to graphane formation, large perfect graphone-like domains are unlikely to be formed. These findings are especially important since experiments have showed that cluster formation influences the electronic transport properties in hydrogenated graphene.
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Liang, Hanyang. "Research Progress of Graphene Thin Films for Heat Dissipation Applications in Electronic Devices." Academic Journal of Science and Technology 12, no. 1 (August 20, 2024): 347–50. http://dx.doi.org/10.54097/20shxr21.
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Owing to its superior thermal conductivity, graphen e films excel in heat transfer and dispersion, enhancing the efficiency of electronic devices in dissipating heat. Various graphene-based composite materials are created by blending with other substances, catering to diverse needs. Currently, graphene's production process is well-established, with several composites performing well. Nonetheless, achieving widespread production and production of graphene, along with the effective management and refinement of interfacial thermal resistance, remains a challenge.
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Mihet, Maria, Monica Dan, and Mihaela D. Lazar. "CO2 Hydrogenation Catalyzed by Graphene-Based Materials." Molecules 27, no. 11 (May 24, 2022): 3367. http://dx.doi.org/10.3390/molecules27113367.
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In the context of an increased interest in the abatement of CO2 emissions generated by industrial activities, CO2 hydrogenation processes show an important potential to be used for the production of valuable compounds (methane, methanol, formic acid, light olefins, aromatics, syngas and/or synthetic fuels), with important benefits for the decarbonization of the energy sector. However, in order to increase the efficiency of the CO2 hydrogenation processes, the selection of active and selective catalysts is of utmost importance. In this context, the interest in graphene-based materials as catalysts for CO2 hydrogenation has significantly increased in the last years. The aim of the present paper is to review and discuss the results published until now on graphene-based materials (graphene oxide, reduced graphene oxide, or N-dopped graphenes) used as metal-free catalysts or as catalytic support for the thermocatalytic hydrogenation of CO2. The reactions discussed in this paper are CO2 methanation, CO2 hydrogenation to methanol, CO2 transformation into formic acid, CO2 hydrogenation to high hydrocarbons, and syngas production from CO2. The discussions will focus on the effect of the support on the catalytic process, the involvement of the graphene-based support in the reaction mechanism, or the explanation of the graphene intervention in the hydrogenation process. Most of the papers emphasized the graphene’s role in dispersing and stabilizing the metal and/or oxide nanoparticles or in preventing the metal oxidation, but further investigations are needed to elucidate the actual role of graphenes and to propose reaction mechanisms.
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RAO, C. N. R., K. S. SUBRAHMANYAM, H. S. S. RAMAKRISHNA MATTE, and A. GOVINDARAJ. "GRAPHENE: SYNTHESIS, FUNCTIONALIZATION AND PROPERTIES." Modern Physics Letters B 25, no. 07 (March 20, 2011): 427–51. http://dx.doi.org/10.1142/s0217984911025961.
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Graphenes with varying number of layers can be synthesized by different strategies. Thus, single-layer graphene is obtained by the reduction of single layer graphene oxide, CVD and other methods besides micromechanical cleavage. Few-layer graphenes are prepared by the conversion of nanodiamond, arc-discharge of graphite and other means. We briefly present the various methods of synthesis and the nature of graphenes obtained. We then discuss the various properties of graphenes. The remarkable property of graphene of quenching fluorescence of aromatic molecules is shown to be associated with photo-induced electron transfer, on the basis of fluorescence decay and time-resolved transient absorption spectroscopic measurements. The interaction of electron donor and acceptor molecules with few-layer graphene samples has been discussed. Decoration of metal nano-particles on graphene sheets and the resulting changes in electronic structure are examined. Few-layer graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Graphene-like MoS 2 and WS 2 have been prepared by chemical methods, and the materials are characterized by electron microscopy, atomic force microscopy (AFM) and other methods. Boron nitride analogues of graphene have been obtained by a simple chemical procedure starting with boric acid and urea and have been characterized by various techniques.
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RAO, C. N. R., K. S. SUBRAHMANYAM, H. S. S. RAMAKRISHNA MATTE, URMIMALA MAITRA, KOTA MOSES, and A. GOVINDARAJ. "GRAPHENE: SYNTHESIS, FUNCTIONALIZATION AND PROPERTIES." International Journal of Modern Physics B 25, no. 30 (December 10, 2011): 4107–43. http://dx.doi.org/10.1142/s0217979211059358.
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Graphenes with varying number of layers can be synthesized by different strategies. Thus, single-layer graphene is obtained by the reduction of single layer graphene oxide, CVD and other methods besides micromechanical cleavage. Few-layer graphenes are prepared by the conversion of nanodiamond, arcdischarge of graphite and other means. We briefly present the various methods of synthesis and the nature of graphenes obtained. We then discuss the various properties of graphenes. The remarkable property of graphene of quenching fluorescence of aromatic molecules is shown to be associated with photo-induced electron transfer, on the basis of fluorescence decay and time-resolved transient absorption spectroscopic measurements. The interaction of electron donor and acceptor molecules with few-layer graphene samples has been discussed. Decoration of metal nano-particles on graphene sheets and the resulting changes in electronic structure are examined. Few-layer graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Graphene-like MoS 2 and WS 2 have been prepared by chemical methods, and the materials are characterized by electron microscopy, atomic force microscopy (AFM) and other methods. Boron nitride analogues of graphene have been obtained by a simple chemical procedure starting with boric acid and urea and have been characterized by various techniques.
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K. Edaan Al-mashaal, Asaad. "BENDING OF GRAPHENE VIA ELECTROSTATIC ACTUATION." International Journal Multidisciplinary (IJMI) 1, no. 4 (December 4, 2024): 28–41. https://doi.org/10.61796/ijmi.v1i4.239.
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Objective: To explore the potential of graphene in electrostatic actuation, emphasizing its mechanisms, applications, and challenges, and to evaluate its integration with MEMS/NEMS technologies. Method: A detailed literature review was conducted, analyzing the principles of electrostatic actuation and graphene's unique properties. The study examined synthesis and fabrication methods, focusing on scalability, quality control, and defect minimization. Performance metrics such as actuation efficiency, mechanical strain, and response time were also evaluated using data from prior experimental and theoretical studies. Results: Graphene’s exceptional electrical, mechanical, and thermal properties make it a promising material for electrostatic actuators. It demonstrates significant potential in MEMS/NEMS devices, flexible electronics, and biomedical applications. However, challenges persist in achieving consistent large-scale production, minimizing defects, and improving actuation efficiency. The review identifies key strategies for enhancing scalability and stability while maintaining graphene's functional properties. Novelty: This study provides a comprehensive review of graphene-based electrostatic actuators, integrating insights into their mechanisms, synthesis, fabrication challenges, and application prospects. It highlights innovative strategies to overcome existing limitations, offering a roadmap for advancing the practical implementation of graphene in actuator technologies.
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J, Monica, and Divyasankari G. "Experimental Study on Green Concrete using Graphene." International Journal of Innovative Research in Advanced Engineering 10, no. 07 (July 31, 2023): 486–89. http://dx.doi.org/10.26562/ijirae.2023.v1007.07.
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The paper considers methods for concrete modification using low-layer graphene and grapheme oxide. It was found that graphene oxide and low-layer graphene obtained by liquid-phase shear exfoliation significantly increase the strength of concrete. In our opinion, low-layer graphene has better prospects since it is cheaper and its production technology is environmentally friendly. The viability and future of graphene largely depends on the availability of such a method that allows mass production of high-quality graphene at an affordable price. In this regard, liquid- phase separation of graphite with the formation of low-layer graphene, which can be used to modify concrete, turned out to be a competitive solution. The following main tasks were formulated in order to solve the organizational problems of low- layer grapheme industrial production: reducing the concentration of low-layer grapheme in concrete; increasing the concentration of low-layer graphene in suspension; developing an industrial technology for the production of concentrate with a high content of low- layer graphene; conducting full-scale experimental studies to determine the optimal concentration of low-layer graphene in concrete.
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Wang, Xuan Lun, and Wei Jiu Huang. "Fabrication and Characterization of Graphene/Polyimide Nanocomposites." Advanced Materials Research 785-786 (September 2013): 138–44. http://dx.doi.org/10.4028/www.scientific.net/amr.785-786.138.
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Graphene/polyimide nanocomposites with different weight loadings were prepared by a solution compounding technique. Graphene was synthesized from graphite oxide that was fabricated by the Hummers method. X-ray diffraction (XRD), ultraviolet visible (UV-vis) spectra and simultaneous thermal analysis were used for the microstructure analysis of the graphenes. Graphenes with single layer structure were synthesized successfully and had good solubility in water or other polar solvents due to a few functional groups on the graphene carbons. Graphenes have good thermal stability. Mechanical and tribological properties were studied for the graphene/polyimide composites. The composites have excellent strength and toughness with very small graphene loading level and the addition of graphene decreased the friction coefficient and wear rate of the composites.
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Majidi, Roya. "Electronic properties of porous graphene, α-graphyne, graphene-like, and graphyne-like BN sheets." Canadian Journal of Physics 94, no. 3 (March 2016): 305–9. http://dx.doi.org/10.1139/cjp-2015-0445.
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We have used density functional theory to investigate the electronic properties of two-dimensional porous sheets. The porous C and BN sheets based on graphene and α-graphyne are studied. It is found that the porous graphene is an insulator while porous α-graphyne has semiconducting properties. By substitution of C atoms by B and N atoms, the band gap becomes larger. The porous graphene-like and porous graphyne-like BN sheets show insulating behaviors. The nonzero band gap of these porous C and BN sheets may provide an opportunity to use them in nanoelectronic devices.
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Bouša, D., J. Luxa, V. Mazánek, O. Jankovský, D. Sedmidubský, K. Klímová, M. Pumera, and Z. Sofer. "Toward graphene chloride: chlorination of graphene and graphene oxide." RSC Advances 6, no. 71 (2016): 66884–92. http://dx.doi.org/10.1039/c6ra14845j.
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Chlorinated graphene derivates with chlorine concentration exceeding 11 at% were synthesized by high temperature exfoliation in chlorine atmosphere. Halogen graphenes have a great potential for electronic and electrochemical devices.
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Suh, JY, SE Shin, and DH Bae. "Electrical properties of polytetrafluoroethylene/few-layer graphene composites fabricated by solid-state processing." Journal of Composite Materials 51, no. 18 (October 13, 2016): 2565–73. http://dx.doi.org/10.1177/0021998316674349.
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High electrical performances of polytetrafluoroethylene composites containing few-layer graphenes are established by solid-state processing. Polytetrafluoroethylene and FLG powders are mechanically mixed without solvents at room temperature, and hot-pressed. Few-layer graphenes are attached to the polytetrafluoroethylene powder, and gradually wrap the powder surface during milling with a low milling speed. The few-layer graphene-wrapped polytetrafluoroethylene powders readily facilitate the formation of a continuous few-layer graphene network due to the contact between adjacent few-layer graphene-wrapped powders. The final composites using few-layer graphene-wrapped polytetrafluoroethylene powders include a three-dimensional conducting network. Eventually, the wrapping morphology of the polytetrafluoroethylene/few-layer graphene powder results in a remarkable electrical conductivity of 7353 Sm−1 at 30 vol. %. few-layer graphene loading.
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Ooi, Kelvin J. A., and Dawn T. H. Tan. "Nonlinear graphene plasmonics." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 473, no. 2206 (October 2017): 20170433. http://dx.doi.org/10.1098/rspa.2017.0433.
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The rapid development of graphene has opened up exciting new fields in graphene plasmonics and nonlinear optics. Graphene's unique two-dimensional band structure provides extraordinary linear and nonlinear optical properties, which have led to extreme optical confinement in graphene plasmonics and ultrahigh nonlinear optical coefficients, respectively. The synergy between graphene's linear and nonlinear optical properties gave rise to nonlinear graphene plasmonics, which greatly augments graphene-based nonlinear device performance beyond a billion-fold. This nascent field of research will eventually find far-reaching revolutionary technological applications that require device miniaturization, low power consumption and a broad range of operating wavelengths approaching the far-infrared, such as optical computing, medical instrumentation and security applications.
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Murav’ev, V. V., and V. M. Mishchenka. "Ab-initio simulation of hydrogenated graphene properties." Doklady BGUIR 19, no. 8 (January 1, 2022): 5–9. http://dx.doi.org/10.35596/1729-7648-2021-19-8-5-9.
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Ab-initio simulation of hydrogenated graphene properties was performed. At present, graphene is considered one of the most promising materials for the formation of new semiconductor devices with good characteristics. Graphene has been the subject of many recent investigations due to its peculiar transport, mechanical and others properties [1]. The chemical modification of graphene named as graphane has recently entered the investigation as a possible candidate to solve problems connected with the lack of a graphene bandgap. Graphane is a compound material consisting of two-dimensional graphene bonded by some atoms of hydrogen. The investigation shows that graphane has the three valley Г-М-K band structure with the Г valley, which has the smallest energy gap between the conductivity zone and the valence zone. The calculation of relative electron masses and non-parabolic coefficients in Г, М and K valleys was performed. Based on the obtained characteristics, it is possible to implement a statistical multi-particle Monte Carlo method to determine the characteristics of electron transfer in heterostructure semiconductor devices. A research on modified graphene structures is important for fundamental science and technological applications in high-speed transistor structures operating in the microwave and very high frequency ranges.
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Huang, Jing, and Jun Kang. "Two-dimensional graphyne–graphene heterostructure for all-carbon transistors." Journal of Physics: Condensed Matter 34, no. 16 (February 22, 2022): 165301. http://dx.doi.org/10.1088/1361-648x/ac513b.
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Abstract Semiconducting graphyne is a two-dimensional (2D) carbon allotrope with high mobility, which is promising for next generation all-carbon field effect transistors (FETs). In this work, the electronic properties of van der Waals heterostructure consists of 2D graphyne and graphene (GY/G) were studied from first-principles calculations. It is found that the band dispersion of isolated graphene and graphyne remain intact after they were stacked together. Due to the charge transfer from graphene to graphyne, the Fermi level of the GY/G heterostructure crosses the VB of graphene and the CB of graphyne. As a result, n-type Ohmic contact with zero Schottky barrier height (SBH) is obtained in GY/G based FETs. Moreover, the electron tunneling from graphene to graphyne is found to be efficient. Therefore, excellent electron transport properties can be expected in GY/G based FETs. Lastly, it is demonstrated that the SBH in the GY/G heterostructure can be tune by applying a vertical external electric field or doping, and the transition from n-type to p-type contact can be realized. These results show that GY/G is potentially suitable for 2D FETs, and provide insights into the development of all-carbon electronic devices.
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Ma, Wen Shi, Jun Wen Zhou, and Xiao Dan Lin. "X-Ray Photoelectron Spectroscopy Study on Reduction of Graphene Oxide with Hydrazine Hydrate." Advanced Materials Research 287-290 (July 2011): 539–43. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.539.
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Graphene oxide was prepared through Hummers' method，then different reduced graphenes were prepared via reduction of graphene oxide with hydrazine hydrate for 1h、12h and 24h. X-ray photoelectron spectroscopy (XPS) was used for the characterization of graphene oxide and the reduced graphenes. The variation of the contents of carbon in carbon and oxygen functional groups and chemical compositions of graphene oxides were investigated through analysis the content of different carbon atoms in different reduced graphenes. The results showed that the reduction reaction was very fast in the first 1 h, the content of total oxygen bonded carbon atoms decreased from 83.6% to 22.1%, and then after the reduction rate became very slow. After 12h, the content of total oxygen bonded carbon atom is 19.56%, only 2.54% lower than that of 1h’s. At the same time, C-N was introduced in the graphene oxides; this increased the stereo-hindrance for hydrazine hydrate attacking the C-Oxygen groups, thus reduced the reduction rate. After reduction for 24h, there still exists 16.4% oxygen bonded carbon atoms and the total conversion ratio of graphene approaches 70%.
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Bhattarai, Laxmi Nath. "Graphene: A Peculiar Allotrope Of Carbon." Himalayan Physics 3 (January 1, 2013): 87–88. http://dx.doi.org/10.3126/hj.v3i0.7314.
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Graphene is a two dimensional one atom thick allotrope of Carbon. Electrons in grapheme behave as massless relativistic particles. It is a 2 dimensional nanomaterial with many peculiar properties. In grapheme both integral and fractional quantum Hall effects are observed. Many practical application are seen from use of Graphene material.The Himalayan PhysicsVol. 3, No. 3, July 2012Page: 87-88
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Li, Xiaomeng, Xiufang Chen, Xiangang Xu, Xiaobo Hu, and Zhiyuan Zuo. "Enhanced Performance of a Visible Light Detector Made with Quasi-Free-Standing Graphene on SiC." Materials 12, no. 19 (October 2, 2019): 3227. http://dx.doi.org/10.3390/ma12193227.
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The excellent optoelectronic properties of graphene give it great potential for applications in optical detection. Among the graphenes obtained through many synthetic methods, epitaxial graphene obtained by thermal decomposition on silicon carbide has remarkable advantages for preparing photodetectors. In this research, epitaxial graphene has been successfully prepared on a silicon surface (0001) of semi-insulating 4H-SiC substrate with a size of 10 mm × 10 mm and epitaxial graphene has been converted to quasi-free-standing graphene by hydrogen passivation. Two metal-graphene-metal photodetectors were fabricated using the two types of graphenes above and the photo-absorption properties of detectors have been investigated under 650-nm laser illumination with different illumination powers. From a comparison of the performances between the two detectors, it was found that a photodetector fabricated with quasi-free-standing graphene shows enhanced performance under a light power of 0.018 mW. Responsivity and external quantum efficiency reach maxima of 5.11 A/W and 9.74%, respectively. This dramatic improvement is mainly due to the disappearance of the buffer layer in epitaxial graphene, providing a new method to achieve optimization of graphene-based opto-electrical devices.
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Strankowski, Michał, Damian Włodarczyk, Łukasz Piszczyk, and Justyna Strankowska. "Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies." Journal of Spectroscopy 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/7520741.
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Recently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal of the oxide groups can create vacancies and structural defects, reduced graphene oxide (rGO) is used in composites as effective filler similar to GO. Authors developed a new polyurethane nanocomposite using a derivative of grapheme, thermally reduced graphene oxide (rGO), to modify the matrix of polyurethane elastomers, by rGO.
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Abdelnabi, Mahmoud Mohamed Saad, Chiara Izzo, Elena Blundo, Maria Grazia Betti, Marco Sbroscia, Giulia Di Bella, Gianluca Cavoto, et al. "Deuterium Adsorption on Free-Standing Graphene." Nanomaterials 11, no. 1 (January 8, 2021): 130. http://dx.doi.org/10.3390/nano11010130.
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A suitable way to modify the electronic properties of graphene—while maintaining the exceptional properties associated with its two-dimensional (2D) nature—is its functionalisation. In particular, the incorporation of hydrogen isotopes in graphene is expected to modify its electronic properties leading to an energy gap opening, thereby rendering graphene promising for a widespread of applications. Hence, deuterium (D) adsorption on free-standing graphene was obtained by high-energy electron ionisation of D2 and ion irradiation of a nanoporous graphene (NPG) sample. This method allows one to reach nearly 50 at.% D upload in graphene, higher than that obtained by other deposition methods so far, towards low-defect and free-standing D-graphane. That evidence was deduced by X-ray photoelectron spectroscopy of the C 1s core level, showing clear evidence of the D-C sp3 bond, and Raman spectroscopy, pointing to remarkably clean and low-defect production of graphane. Moreover, ultraviolet photoelectron spectroscopy showed the opening of an energy gap in the valence band. Therefore, high-energy electron ionisation and ion irradiation is an outstanding method for obtaining low defect D-NPG with a high D upload, which is very promising for the fabrication of semiconducting graphane on large scale.
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Abdelnabi, Mahmoud Mohamed Saad, Chiara Izzo, Elena Blundo, Maria Grazia Betti, Marco Sbroscia, Giulia Di Bella, Gianluca Cavoto, et al. "Deuterium Adsorption on Free-Standing Graphene." Nanomaterials 11, no. 1 (January 8, 2021): 130. http://dx.doi.org/10.3390/nano11010130.
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A suitable way to modify the electronic properties of graphene—while maintaining the exceptional properties associated with its two-dimensional (2D) nature—is its functionalisation. In particular, the incorporation of hydrogen isotopes in graphene is expected to modify its electronic properties leading to an energy gap opening, thereby rendering graphene promising for a widespread of applications. Hence, deuterium (D) adsorption on free-standing graphene was obtained by high-energy electron ionisation of D2 and ion irradiation of a nanoporous graphene (NPG) sample. This method allows one to reach nearly 50 at.% D upload in graphene, higher than that obtained by other deposition methods so far, towards low-defect and free-standing D-graphane. That evidence was deduced by X-ray photoelectron spectroscopy of the C 1s core level, showing clear evidence of the D-C sp3 bond, and Raman spectroscopy, pointing to remarkably clean and low-defect production of graphane. Moreover, ultraviolet photoelectron spectroscopy showed the opening of an energy gap in the valence band. Therefore, high-energy electron ionisation and ion irradiation is an outstanding method for obtaining low defect D-NPG with a high D upload, which is very promising for the fabrication of semiconducting graphane on large scale.
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Liu, Li, and Chang Chun Zhou. "Preparation and Application of Grapheme." Applied Mechanics and Materials 670-671 (October 2014): 127–29. http://dx.doi.org/10.4028/www.scientific.net/amm.670-671.127.
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Graphene is a kind of new carbon material with isomer. Its basic structure is composed of six carbon atoms in closed loop structure. In order to make graphene with excellent properties in practical application, people have proposed various methods of preparing grapheme. Graphene shows promising applications in solar cell. This paper introduced preparation and applications of graphene in the high-tech fields.
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Qu, Li-Hua, Xiao-Long Fu, Chong-Gui Zhong, Peng-Xia Zhou, and Jian-Min Zhang. "Equibiaxial Strained Oxygen Adsorption on Pristine Graphene, Nitrogen/Boron Doped Graphene, and Defected Graphene." Materials 13, no. 21 (November 4, 2020): 4945. http://dx.doi.org/10.3390/ma13214945.
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We report first-principles calculations on the structural, mechanical, and electronic properties of O2 molecule adsorption on different graphenes (including pristine graphene (G–O2), N(nitrogen)/B(boron)-doped graphene (G–N/B–O2), and defective graphene (G–D–O2)) under equibiaxial strain. Our calculation results reveal that G–D–O2 possesses the highest binding energy, indicating that it owns the highest stability. Moreover, the stabilities of the four structures are enhanced enormously by the compressive strain larger than 2%. In addition, the band gaps of G–O2 and G–D–O2 exhibit direct and indirect transitions. Our work aims to control the graphene-based structure and electronic properties via strain engineering, which will provide implications for the application of new elastic semiconductor devices.
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Colmiais, Ivo, Vitor Silva, Jérôme Borme, Pedro Alpuim, and Paulo M. Mendes. "Extraction of Graphene’s RF Impedance through Thru-Reflect-Line Calibration." Micromachines 14, no. 1 (January 14, 2023): 215. http://dx.doi.org/10.3390/mi14010215.
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Graphene has unique properties that can be exploited for radiofrequency applications. Its characterization is key for the development of new graphene devices, circuits, and systems. Due to the two-dimensional nature of graphene, there are challenges in the methodology to extract relevant characteristics that are necessary for device design. In this work, the Thru-Reflect-Line (TRL) calibration was evaluated as a solution to extract graphene’s electrical characteristics from 1 GHz to 65 GHz, where the calibration structures’ requirements were analyzed. It was demonstrated that thick metallic contacts, a low-loss substrate, and a short and thin contact are necessary to characterize graphene. Furthermore, since graphene’s properties are dependent on the polarization voltage applied, a backgate has to be included so that graphene can be characterized for different chemical potentials. Such characterization is mandatory for the design of graphene RF electronics and can be used to extract characteristics such as graphene’s resistance, quantum capacitance, and kinetic inductance. Finally, the proposed structure was characterized, and graphene’s resistance and quantum capacitance were extracted.
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Karimi, Samira, Emna Helal, Giovanna Gutierrez, Nima Moghimian, Milad Madinehei, Eric David, Mazen Samara, and Nicole Demarquette. "A Review on Graphene’s Light Stabilizing Effects for Reduced Photodegradation of Polymers." Crystals 11, no. 1 (December 22, 2020): 3. http://dx.doi.org/10.3390/cryst11010003.
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Graphene, the newest member of the carbon’s family, has proven its efficiency in improving polymers’ resistance against photodegradation, even at low loadings equal to 1 wt% or lower. This protective role involves a multitude of complementary mechanisms associated with graphene’s unique geometry and chemistry. In this review, these mechanisms, taking place during both the initiation and propagation steps of photodegradation, are discussed concerning graphene and graphene derivatives, i.e., graphene oxide (GO) and reduced graphene oxide (rGO). In particular, graphene displays important UV absorption, free radical scavenging, and quenching capabilities thanks to the abundant π-bonds and sp2 carbon sites in its hexagonal lattice structure. The free radical scavenging effect is also partially linked with functional hydroxyl groups on the surface. However, the sp2 sites remain the predominant player, which makes graphene’s antioxidant effect potentially stronger than rGO and GO. Besides, UV screening and oxygen barriers are active protective mechanisms attributed to graphene’s high surface area and 2D geometry. Moreover, the way that graphene, as a nucleating agent, can improve the photostability of polymers, have been explored as well. These include the potential effect of graphene on increasing polymer’s glass transition temperature and crystallinity.
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Neto, Antonio Castro, and Andre Geim. "Graphene: Graphene's properties." New Scientist 214, no. 2863 (May 2012): iv—v. http://dx.doi.org/10.1016/s0262-4079(12)61116-6.
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Abdullah, M. M., Rashid Nizam, Hasan B. Albargi, Mohammad Zaki Ahmad, Javed Ahmad, Mohd Farhan Khan, and Jawed Mustafa. "Power Spectrum of Dual Varieties of Graphene Allotropes." Journal of Nanoelectronics and Optoelectronics 18, no. 2 (February 1, 2023): 160–67. http://dx.doi.org/10.1166/jno.2023.3384.
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Graphene is a well-known substance with multiple functions. It has potential applications in electronic and optoelectronic devices. Two graphene sheets have been selected for the present investigation: one graphene model and another with a Stone-Wales defect model. Both the graphenes are heated at different temperatures with the help of the Nose-Hoover method up to 50000 steps. Then different potentials of each are calculated at different temperatures. It has been noted that each graphene first exhibits significant changes at various potentials before becoming consistent at a specific temperature. Similarly, the total energy of both graphenes is calculated and presented. The phonon spectral densities of both models, viz., graphene and graphene with the Stone-Wales defect, were computed with the help of linear response theory. Four major peaks are observed in each graphene and in the graphene with the Stone-Wales defect after heating at different temperatures. The presented peaks of graphene and graphene with the Stone-Wales defect are moving left with an increase in temperature. Further, the calculated peaks are decreasing in strength with an increase in temperature. Before heating the carbon, atoms are tightly bound and can move up and down with full strength since the forces of attraction will be the same from every site of atom position. After heating, the positions of the atoms change, which changes the forces of attraction at different sites. Thus, atoms are vibrating in a certain area only, or the atom breaks up from its parent.
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Pumera, Martin, and Colin Hong An Wong. "Graphane and hydrogenated graphene." Chemical Society Reviews 42, no. 14 (2013): 5987. http://dx.doi.org/10.1039/c3cs60132c.
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Xiao, Zhen Hui, Shui Sheng Wu, Yan Lin Sun, Yu Lin Zhao, and Ya Ming Wang. "Microwave-Hydrothermal Synthesis and Characterization of Graphene." Advanced Materials Research 602-604 (December 2012): 917–20. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.917.
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Graphene was synthesized by microwave-hydrothermal chemical reduction of graphite oxide using hydrazine hydrate as the reducing agent. Graphene was characterized using X-ray diffraction, UV-visible spectrum, FT-IR spectrum and scanning electron microscopy. Results indicated that the as-prepared graphene was wrinkled and comprised fewer graphenes with a highly crystalline structure.
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S, Srinivasan, Sanjana G, and Abinaya P. "A Study of Graphene Applications." Bulletin of Scientific Research 1, no. 1 (May 30, 2019): 47–53. http://dx.doi.org/10.34256/bsr1917.
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Carbon is unique in its own ways, the most special attribute of carbon is that it can make rings and long chain; even life on the earth is possible due to this property of carbon. Graphene is the first two dimensional material and it has many outstanding properties which have resulted in many exciting applications. Graphene is claimed to be so versatile that it will be able to replace present day materials. It is thought to be the perfect two-dimensional carbon crystal as it is the unique blend of properties both mechanical and electronics. Graphene is the thinnest, highly elastic, am bipolar, chemically inert, and hydrophobic, possesses record electron conductivity, high value of mobility, high thermal conductivity, high opacity, low resistivity and shows fractional quantum Hall effect and ballistic conduction and many other interesting properties that are yet be explored. Recently it has been found that the magnetic field of grapheme can be switched on and off. In this paper, I have done a comparative study of properties of grapheme and tried to produce an application of grapheme in two fields which affect us most, that are, Medicine and Electronics.
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Shi, Feng Hui, Jia Li, Bao Yan Zhang, Xue Shi Qiu, and Liang Yong Gu. "Preparation and Electrical Properties of Graphene/PEK-c Films." Advanced Materials Research 1102 (May 2015): 107–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1102.107.
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This article shows us a way to disperse graphene with PEK-c and a method to make graphene/PEK-c films with great surface conductivity. The characterization of grapheme was analyzed by scanning electron microscope (SEM) as well as chloroform without dispersant was identified to be the suitable system to disperse graphene. Graphene/PEK-c films are fabricated in a large scale using coating method. The conductivity of the films were tested by surface resistance tester as well as the surface resistance of graphene/PEK-c film with 50%wt graphene is about 50Ω/sq. Micro cracks were observed by SEM images that were the main reasons to explain the performance differences between real and theoretical conductivity.
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CHANG, WIN-JIN, and HAW-LONG LEE. "FREE ASYMMETRIC TRANSVERSE VIBRATION OF CIRCULAR MONOLAYER GRAPHENE." Nano 09, no. 07 (October 2014): 1450072. http://dx.doi.org/10.1142/s1793292014500726.
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The free vibration equations of circular monolayer graphene are analytically derived based on nonlocal elasticity theory. The natural frequency and mode shape for the axisymmetric and asymmetric circular monolayer graphenes are analyzed using the equations. The results show that the natural frequency of the asymmetric graphene is larger than that of the axisymmetric one. The natural frequency decreases with increasing nonlocal parameter for the axisymmetric and asymmetric graphenes. In addition, the diametrical nodal lines and nodal circles for the flexural vibration of the circular monolayer graphene are investigated. To avoid vibration failure of the sensors, they can be placed at the diametrical nodal lines and nodal circles.
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Apriansyah, Muh, Ananda Galang Wangsa, Muhamad Ukkasya, Fadlun Fadlun, and Nur Anisah. "STUDY LITERATUR : GRAPHENE, NANO TEKNOLOGI SEBAGAI MATERIAL KONSTRUKSI MASA DEPAN." Bearing : Jurnal Penelitian dan Kajian Teknik Sipil 9, no. 1 (July 1, 2024): 1. http://dx.doi.org/10.32502/jbearing.v9i1.8283.
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The development of science and technology encourages progress in various fields, especially through academic innovation. In 2010, Andre K. Geim and Konstantin Novoselov won the Nobel for their discovery of graphene; using tape and graphite. Graphen, known as nanotechnology; superior, has conductive, strong and elastic properties, with these superior properties making graphen a material that has great potential for use in construction activities, such as steel wire ropes for bridges. NASA plans a lift to space using graphene; because of his strength. This research analyzes publications from various sources such as Google Scholar, Dimension, and Research Gate, exploring the attributes of graphene and its derivatives to improve the properties of composite cements and future construction. With the same basic properties as Graphene, Graphene oxide (GO) is also able to increase the compressive, tensile and ductility strength of concrete, reduce cracking, provide electrical conductivity, increase corrosion resistance, and improve the workability of the concrete mixture. Although its use in construction has great potential to overcome future construction problems. However, to be able to use graphene in construction activities, it still requires a lot of development and research.
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First, Phillip N., Walt A. de Heer, Thomas Seyller, Claire Berger, Joseph A. Stroscio, and Jeong-Sun Moon. "Epitaxial Graphenes on Silicon Carbide." MRS Bulletin 35, no. 4 (April 2010): 296–305. http://dx.doi.org/10.1557/mrs2010.552.
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AbstractThis article reviews the materials science of graphene grown epitaxially on the hexagonal basal planes of SiC crystals and progress toward the deterministic manufacture of graphene devices. We show that the growth of epitaxial graphene on Si-terminated SiC(0001) differs from growth on the C-terminated SiC(0001) surface, resulting in, respectively, strong and weak coupling to the substrate and to successive graphene layers. Monolayer epitaxial graphene on either surface displays the expected electronic structure and transport characteristics of graphene, but the non-graphitic stacking of multilayer graphene on SiC(0001) determines an electronic structure much different from that of graphitic multilayers on SiC(0001). This materials system is rich in subtleties, and graphene grown on the two polar faces of SiC differs in important ways, but all of the salient features of ideal graphene are found in these epitaxial graphenes, and wafer-scale fabrication of multi-GHz devices already has been achieved.
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Rahman, Fahrin, Md Saidur Rahman, Rubab Ahmmed, and Md Hazrat Ali. "Quantum Capacitance and Fermi Level Change in Graphene nanoribbons due to Gas Sensing." International Journal of Applied and Structural Mechanics, no. 31 (January 19, 2023): 1–9. http://dx.doi.org/10.55529/ijasm.31.1.9.
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Here we used semiempirical computations to examine the property of nanoribbon of Graphene as a gas sensor with interaction of H2O gas molecule for both pure and defective GNRs which has been generated in Atomistix Toolkit (ATK) software. Density of States GNR before and after the interaction is shown in a (DOS) diagram with gas particles was discovered to be different which has been observed in MATLAB software. It's vital to look at the quantum capacitance when examining Graphene’s electrical properties. So, this study looked at change in quantum capacitance and Fermi Level of Graphene before and after gas sensing and the results were produced with necessary equations. Using a three-electrode electrochemical setup, we are able to directly quantify Graphene's quantum capacitance as a function of gate potential. If Graphene is used in a highly sensitive capacitive circuit, the change in Fermi energy was determined from experimental data of changed Density of States (DOS). Although this research has some limitations and future scopes, we can propose that the change in Fermi Energy level can be approximately 9.5 eV with respect to the quantum capacitance of fabricated Graphene interacting with H2O which is used as a MOSFET in this work.
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Rahman, Fahrin, Md Saidur Rahman, Rubab Ahmmed Ahmmed, and Md Hazrat Ali. "Quantum Capacitance and Fermi Level Change in Graphene nanoribbons due to Gas Sensing." International Journal of Applied and Structural Mechanics, no. 31 (January 19, 2023): 1–9. http://dx.doi.org/10.55529/ijasm31.1.9.
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Here we used semiempirical computations to examine the property of nanoribbon of Graphene as a gas sensor with interaction of H2O gas molecule for both pure and defective GNRs which has been generated in Atomistix Toolkit (ATK) software. Density of States GNR before and after the interaction is shown in a (DOS) diagram with gas particles was discovered to be different which has been observed in MATLAB software. It's vital to look at the quantum capacitance when examining Graphene’s electrical properties. So, this study looked at change in quantum capacitance and Fermi Level of Graphene before and after gas sensing and the results were produced with necessary equations. Using a three-electrode electrochemical setup, we are able to directly quantify Graphene's quantum capacitance as a function of gate potential. If Graphene is used in a highly sensitive capacitive circuit, the change in Fermi energy was determined from experimental data of changed Density of States (DOS). Although this research has some limitations and future scopes, we can propose that the change in Fermi Energy level can be approximately 9.5 eV with respect to the quantum capacitance of fabricated Graphene interacting with H2O which is used as a MOSFET in this work.
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Lee, Haw-Long, and Win-Jin Chang. "Vibrational Analysis of a Single-Layered Nanoporous Graphene Membrane." Nano 11, no. 04 (April 2016): 1650043. http://dx.doi.org/10.1142/s1793292016500430.
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In this study, we use the atomic-scale finite element method to investigate the vibrational behavior of the armchair- and zigzag-structured nanoporous graphene layers with simply supported-free-simply supported-free (SFSF) and clamped-free-free-free (CFFF) boundary conditions. The fundamental frequencies computed for the graphene layers without pores are compared with the results of previous studies. We observe very good correspondence of our results with that of the other studies in all the considered cases. For the armchair- and zigzag-structured nanoporous graphenes with SFSF and CFFF boundary conditions, the frequencies decrease with increasing porosity. When the positions of the pores are symmetric with respect to the center of the graphene, the frequency of the zigzag nanoporous graphene is higher than that of the armchair one. To the best of our knowledge, this is first study investigating the relation between the vibrational behavior and porosity of nanoporous graphene layers, which is essential for tuning the material/structural design and exploring new applications for nanoporous graphenes.
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Amalia, Dinda Putri, and Rini Riastuti. "Anticorrosive Epoxy Coatings Enhanced with Rice Husk Derived-Graphene." Jurnal Pendidikan Teknologi Kejuruan 5, no. 2 (July 4, 2022): 35–40. http://dx.doi.org/10.24036/jptk.v5i2.26823.
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Coatings are the most common corrosion control practice. Therefore, it is very important to discover the most cost-effective and environmentally-friendly coating materials for sustainability. When dispersed in epoxy resin, graphene has barrier properties that improve the anticorrosive performance of the metal significantly. Graphene can be synthesized from agricultural waste. Herein, graphene derived from rice husk and epoxy resin was developed with solution mixing to prepare graphene-epoxy coating composites with enhanced anti-corrosive properties. X-ray diffraction, UV-vis spectroscopy, and scanning electron microscopy were used to characterize the synthesized graphenes. The anticorrosive properties of the coatings were characterized by potentiodynamic polarization and electrochemical impedance spectroscopy, which resulted in the corrosion resistance of synthesized graphene and commercial reduced graphene oxide being better than commercial graphene. The impedance and corrosion rate values of synthesized graphene are 1.77 x 105 Ω and 0.00011 mm/year.
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Wang, Hong Jie, Li Guo Jin, Shuo Wang, Chao Wang, and Tai Yang Liu. "Study on Dye-Sensitized Solar Cells Based on Graphene / Pt Counter Electrode." Advanced Materials Research 1056 (October 2014): 25–29. http://dx.doi.org/10.4028/www.scientific.net/amr.1056.25.
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Graphene/platinum composite gel was prepared with chloroplatinic acid and graphene oxide (GO) as precursors by in-situ reduction method. Grapheme/platinum composite film as counter electrode was prepared on fluorine-doped tin oxide (FTO) glass by electro-hydrodynamic (EHD) method. Battery was assembled with nanoTiO2film as anode, N3 dye, and ionic liquid electrolyte. It was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and X-ray Diffraction (XRD). Graphene/platinum composite film include very thin graphene layers, with platinum particles of an average dimension dispersed evenly in graphene layers. This device shows similar photoelectric conversion efficiency compared with platinum electrode under 100 mWcm-2(1 sun) AM1.5 illumination.
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Liu, Aaron, and Qing Peng. "A Molecular Dynamics Study of the Mechanical Properties of Twisted Bilayer Graphene." Micromachines 9, no. 9 (August 31, 2018): 440. http://dx.doi.org/10.3390/mi9090440.
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Graphene is one of the most important nanomaterials. The twisted bilayer graphene shows superior electronic properties compared to graphene. Here, we demonstrate via molecular dynamics simulations that twisted bilayer graphene possesses outstanding mechanical properties. We find that the mechanical strain rate and the presence of cracks have negligible effects on the linear elastic properties, but not the nonlinear mechanical properties, including fracture toughness. The “two-peak” pattern in the stress-strain curves of the bilayer composites of defective and pristine graphene indicates a sequential failure of the two layers. Our study provides a safe-guide for the design and applications of multilayer grapheme-based nanoelectronic devices.
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Bagade, Sonal Santosh, Shashidhar Patel, M. M. Malik, and Piyush K. Patel. "Recent Advancements in Applications of Graphene to Attain Next-Level Solar Cells." C 9, no. 3 (July 19, 2023): 70. http://dx.doi.org/10.3390/c9030070.
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This paper presents an intensive review covering all the versatile applications of graphene and its derivatives in solar photovoltaic technology. To understand the internal working mechanism for the attainment of highly efficient graphene-based solar cells, graphene’s parameters of control, namely its number of layers and doping concentration are thoroughly discussed. The popular graphene synthesis techniques are studied. A detailed review of various possible applications of utilizing graphene’s attractive properties in solar cell technology is conducted. This paper clearly mentions its applications as an efficient transparent conducting electrode, photoactive layer and Schottky junction formation. The paper also covers advancements in the 10 different types of solar cell technologies caused by the incorporation of graphene and its derivatives in solar cell architecture. Graphene-based solar cells are observed to outperform those solar cells with the same configuration but lacking the presence of graphene in them. Various roles that graphene efficiently performs in the individual type of solar cell technology are also explored. Moreover, bi-layer (and sometimes, tri-layer) graphene is shown to have the potential to fairly uplift the solar cell performance appreciably as well as impart maximum stability to solar cells as compared to multi-layered graphene. The current challenges concerning graphene-based solar cells along with the various strategies adopted to resolve the issues are also mentioned. Hence, graphene and its derivatives are demonstrated to provide a viable path towards light-weight, flexible, cost-friendly, eco-friendly, stable and highly efficient solar cell technology.
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Song, Chenglin. "Application prospects of graphene in environmental science." Applied and Computational Engineering 72, no. 1 (July 26, 2024): 35–44. http://dx.doi.org/10.54254/2755-2721/72/20240987.
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Nanomaterials and graphene, as cutting-edge materials, have play a crucial role in environmental governance. The introduction of nanomaterials brings new hope to environmental governance. Graphene not only improves the efficiency and cost-effectiveness of water treatment but also drives innovation and development in environmental technologies. This article provides a summary and analysis review starting from the characteristics of nanomaterials and Graphene, comprehensively reviewing Graphenes advantage in environmental technologies and discovered its application in this area. The research summarized the conclusion that Graphenes characteristics make it suitable for addressing environmental issues such as water pollution, its composites can play an important role in water treatment process including water purification, heavy metal adsorption, organic compound adsorption and removal through different preparation and reaction mechanisms. By introducing Nanopore structures and artificially designed stacking structures on graphene membranes, the permeation performance could be modulated and improved. By the way of physical and chemical adsorption, ion exchange, electrochemical and photocatalysis, Graphene and its oxide could be applied to remove heavy metal ion and organic substances from polluted water. The article also introduced the main preparation methods of Graphene and its potential secondary pollution problem. This article provides valuable insights for scientific research and engineering practices in environmental protection and sustainable development.
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Chakraborty, Pranay, Tengfei Ma, Amir Hassan Zahiri, Lei Cao, and Yan Wang. "Carbon-Based Materials for Thermoelectrics." Advances in Condensed Matter Physics 2018 (July 4, 2018): 1–29. http://dx.doi.org/10.1155/2018/3898479.
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This article reviews the recent progress towards achieving carbon-based thermoelectric materials. A wide range of experimental and computational studies on carbon allotropes and composites is covered in this review paper. Specifically, we discuss the strategies for engineering graphene, graphene nanoribbon, graphene nanomesh, graphene nanowiggle, carbon nanotube (CNT), fullerene, graphyne, and carbon quantum dot for better thermoelectric performance. Moreover, we discuss the most recent advances in CNT/graphene-polymer composites and the related challenges and solutions. We also highlight the important charge and heat transfer mechanisms in carbon-based materials and state-of-the-art strategies for enhancing thermoelectric performance. Finally, we provide an outlook towards the future of carbon-based thermoelectrics.
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Nagappan, Saravanan, Malarkodi Duraivel, SeongHoon Han, Mohammad Yusuf, Manjiri Mahadadalkar, KyeongMun Park, Amarajothi Dhakshinamoorthy, et al. "Electrocatalytic Oxygen Reduction Reaction of Graphene Oxide and Metal-Free Graphene in an Alkaline Medium." Nanomaterials 13, no. 8 (April 8, 2023): 1315. http://dx.doi.org/10.3390/nano13081315.
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Graphene is a well-known two-dimensional material with a large surface area and is used for numerous applications in a variety of fields. Metal-free carbon materials such as graphene-based materials are widely used as an electrocatalyst for oxygen reduction reactions (ORRs). Recently, more attention has been paid to developing metal-free graphenes doped with heteroatoms such as N, S, and P as efficient electrocatalysts for ORR. In contrast, we found our prepared graphene from graphene oxide (GO) by the pyrolysis method under a nitrogen atmosphere at 900 °C has shown better ORR activity in aqueous 0.1 M potassium hydroxide solution electrolyte as compared with the electrocatalytic activity of pristine GO. At first, we prepared various graphene by pyrolysis of 50 mg and 100 mg of GO in one to three alumina boats and pyrolyzed the samples under a N2 atmosphere at 900 °C. The prepared samples are named G50-1B to 3B and G100-1B and G100-2B. The prepared GO and graphenes were also analyzed under various characterization techniques to confirm their morphology and structural integrity. The obtained results suggest that the ORR electrocatalytic activity of graphene may differ based on the pyrolysis conditions. We found that G100-1B (Eonset, E1/2, JL, and n values of 0.843, 0.774, 4.558, and 3.76) and G100-2B (Eonset, E1/2, and JL values of 0.837, 0.737, 4.544, and 3.41) displayed better electrocatalytic ORR activity, as did Pt/C electrode (Eonset, E1/2, and JL values of 0.965, 0.864, 5.222, and 3.71, respectively). These results display the wide use of the prepared graphene for ORR and also can be used for fuel cell and metal–air battery applications.
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Tene, Talia, Stefano Bellucci, Marco Guevara, Fabian Arias Arias, Miguel Ángel Sáez Paguay, John Marcos Quispillo Moyota, Melvin Arias Polanco, et al. "Adsorption of Mercury on Oxidized Graphenes." Nanomaterials 12, no. 17 (August 31, 2022): 3025. http://dx.doi.org/10.3390/nano12173025.
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Graphene oxide (GO) and its reduced form, reduced graphene oxide (rGO), are among the most predominant graphene derivatives because their unique properties make them efficient adsorbent nanomaterials for water treatment. Although extra-functionalized GO and rGO are customarily employed for the removal of pollutants from aqueous solutions, the adsorption of heavy metals on non-extra-functionalized oxidized graphenes has not been thoroughly studied. Herein, the adsorption of mercury(II) (Hg(II)) on eco-friendly-prepared oxidized graphenes is reported. The work covers the preparation of GO and rGO as well as their characterization. In a further stage, the description of the adsorption mechanism is developed in terms of the kinetics, the associated isotherms, and the thermodynamics of the process. The interaction between Hg(II) and different positions of the oxidized graphene surface is explored by DFT calculations. The study outcomes particularly demonstrate that pristine rGO has better adsorbent properties compared to pristine GO and even other extra-functionalized ones.