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Graphite is an allotrope of carbon that occurs naturally. The structure is comprised of multiple layers of carbon atoms that are organized in a hexagonal lattice and are interconnected by relatively weak van der Waals forces. Graphite exhibits favorable electrical conductivity characteristics, demonstrating enhanced efficiency in conducting electricity along its layers as opposed to that perpendicular to the layers. This restriction influences the efficiency of the device within certain electrical and electronic applications. To address these challenges, a range of exfoliation techniques have been employed to achieve the production of graphene with a limited number of layers, typically ranging from single to a few layers. In this study, a straightforward and cost-effective method known as Scotch-Tape Microexfoliation was employed to produce graphene successfully. Optical images were captured to document various iterations of exfoliation. Notably, an increase in the number of iterations yielded a corresponding increase in film transparency, indicating the formation of a monolayer of graphene. Furthermore, the presence of defects in graphene was identified through the observation of the peak corresponding to the D-band in Raman spectroscopy. [ABSTRACT FROM AUTHOR]

The technique of micro-exfoliation has gained prominence as a highly effective and adaptable method for exploiting two-dimensional (2D) materials, such as graphene Transition metal dichalcogenides (TMDCs), Borophene, Molybdenum disulfide (MoS2), among others. This paper presents an analysis of optical images and the micro exfoliation technique, focusing on the application to MoS2 and graphene. Additionally, the study investigates the exfoliated sheet of graphene, MoS2, and their hybrid on a (111) crystal plane of silicon wafer. The micro-exfoliation technique employed for MoS2 involves a mechanical process that gently disentangles the layers of MoS2 from the larger crystal structure, resulting in the formation of ultrathin two-dimensional nanosheets. This paper comprehensively analyses the exfoliation processes' mechanisms, emphasizing the intricate relationship between van der Waals forces, interlayer bonding, and external forces. The micro-mechanical exfoliation, a fundamental technique, entails the utilization of adhesive scotch tape to remove monolayers from a large MoS2 crystal delicately. The integration of MoS2 into various applications such as electronics, optoelectronics, sensors, and energy storage devices has been driven by its exceptional properties, including its distinctive electronic, optical, and mechanical characteristics. Furthermore, the ability to adjust the bandgap of MoS2 has created novel opportunities for potential applications in the field of semiconductors. This paper provides a succinct summary of recent studies, that have concentrated on the optical characterization of MoS2 monolayers. Optical and Raman spectroscopy was employed to characterize the 2D sheets of MoS2 and its hybrid materials. [ABSTRACT FROM AUTHOR]

The detrimental effects of climate change and global warming have become major concerns due to an increase in carbon footprints across the globe. One of the techniques to minimize carbon emissions is the use of clean and green energy while limiting the use of fossil fuels. Interestingly, rechargeable batteries based on lithium-ion technology serve the purpose due to their stability and reliability. In particular, lithium-ion batteries have gained more attention due to their higher energy density, high coulombic efficiency, high discharge power, and longer cycle life. Graphite is still employed as an anode material because of its simple and highly ordered carbon structure. However, the search for new materials and their hybrids cannot be ignored, as graphite's interaction with electrolytes leads to poor performance on prolonged usage. MWNTs (Multi Wall Nano Tubes) exhibit exceptional electrical conductivity, a large surface area, and mechanical strength, contributing to an enhanced lithium storage capacity and rate capability, ultimately leading to improved battery performance. Additionally, we have investigated the material using various characterization techniques to ensure that the materials have been synthesized in the correct phase and purity. [ABSTRACT FROM AUTHOR]

The sol-gel methodology has been extensively utilized in the production of metal oxide solutions, commonly known as sols. This technique represents a cost-effective and facile approach to the production of metal oxide solutions, achieved through the utilization of lower temperatures. Here, this paper presents a cost-effective and straightforward method, referred to as 'gel-cast,' for fabricating tape/film composed of a composite material consisting of alumina (Al2O3) and molybdenum disulfide (MoS2). The composite material was synthesized through the even distribution of MoS2 powder within an alumina sol, which was developed using the sol-gel method. The morphological investigations were undertaken to ascertain the characteristics of the tape/film subsequent to the introduction of additives. The composition of the tape/film was also examined both prior to and following the annealing process. [ABSTRACT FROM AUTHOR]

Industrial applications and fundamental scientific research involving the scalable development of high-quality Molybdenum disulfide (MoS2) nanosheets continue to present significant challenges. MoS2 is a material with a two-dimensional (2D) structure consisting of a single layer of molybdenum atoms positioned between two layers of sulfur atoms. The primary type of bonding present within each layer is primarily covalent in nature, characterized by the formation of robust chemical bonds between the atoms of molybdenum and sulfur. Nevertheless, the predominant driving force behind the interactions among the layers of MoS2 is attributed to van der Waals forces. This study utilizes a top-down approach to synthesize MoS2 nanomaterials from their bulk counterpart. This is achieved through the implementation of grinding via liquid exfoliation and ball milling methods. These methods effectively mitigate the influence of weak van der Waals forces that exist between the layers of MoS2, resulting in the production of nanomaterials derived from their bulk counterparts. This study compared the above methods using Field Emission Scanning Electron Microscopy (FESEM) and X-ray Diffraction (XRD). [ABSTRACT FROM AUTHOR]

The process of single-walled carbon nanotube (SWCNT) formation involves the rolling of a graphene sheet into a cylindrical configuration. The present work provides the construction of single-walled carbon nanotube field-effect transistors (SWCNTFETs) on a silicon oxide (SiO2) wafer using the dielectrophoresis (DEP) technique. In the process of fabricating SWCNTFETs using DEP, semiconducting SWCNTs were incorporated in the role of the active channel component. The length of the channel was measured to be somewhere within a range of 5 µm. The fabrication of the source and drain electrodes involved the use of a 100 nm thick layer of gold (Au) through the implementation of the sputtering technique. The current-voltage (IV) characteristics exhibit a nearly ohmic contact behavior. The utilization of DEP for mounting CNTs is a straightforward and efficient method. Moreover, the manufacturing procedures involved in DEP-based device production are compatible with silicon (Si) technology processes, thereby enabling the potential for large-scale manufacturing of CNT electronic equipment on wafers. Furthermore, the device that was manufactured showed promise for use in a variety of areas, including biosensing, health management, the environment, wearable electronics, etc. [ABSTRACT FROM AUTHOR]