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: The field of nanosensors has been gaining a lot of attention due to its properties such as mechanical and electrical ever since its first discovery by Dr. Wolter and first mechanical sensor in 1994. The rapidly growing demand of nanosensors has become profitable for a multidisciplinary approach in designing and fabrication of materials and strategies for potential applications. Frequent stimulating advancements are being suggested and established in recent years and thus heading towards multiple applications including food safety, healthcare, environmental monitoring, and biomedical research. Nanofabrication being an efficient method has been used in different industries like medical pharmaceutical for their complex functional geometry at a lower scale. These nanofabrications apply through different methods. There are five most commonly known methods which are frequently used, including top-down lithography, molecular self-assembly, bottom-up assembly, heat and pull method for fabrication of biosensors, etching for fabrication of nanosensors etc. Nanofabrication help at the nanoscale to design and work with small models. But these models due to their small size and being sensitive need more care for use as well as more training and experience to do work with. All methods used for nanofabrication are good and helpful. But more preferred is molecular self-assembly as it is helpful in mass production. Nanofabrication has become an emerging and developing field and it assumed that in near future our world is known by the new devices of nanofabrication.

Two-dimensional (2D) materials have exhibited exceptional properties which meet the demands of future applications. These materials appeared after discovery of graphene in 2004 offered such device grade characteristics at nanoscale which did not appear on bulk scale. The research turned to search alternate 2D materials when drawbacks of graphene became surfaced. Despite significant successes and unprecedented efforts which consequent upon several beyond-graphene 2D materials, the complete potentials of such materials are still unexplored which may restrict their usage in devices. This work was carried out with motivation to investigate the thermal stability of several 2D-mono-layered materials including graphene, Borophene, Aluminene, Germanene, BN, SiC and MoS2 based on classical Molecular Dynamics Simulations. Prior to the implementation of the conditions for thermal calculations, the structures were optimized using Geometry-Optimization method. It appeared that all the structural parameters which includes lattice-constant, bond-length and dihedral angles were precisely determined. On the contrary, it was found that several materials beyond graphene can resist up-to certain temperature ranges, depicting the material dependent thermal stability. The radial distribution function (RDF) was calculated which pointed towards thermal broadening, bond breakage and bond formation for the slabs. The RDF-peaks were found to characterize the probability of finding any particle in the nearest neighbors which extend the phenomenon of thermal stability. Thermal stability was compared by plotting the temperature and energy curves from which, the phase transition temperature and heat capacity was determined for the slabs including graphene as benchmark. The phase transition temperatures are found as 4510 K, 2273 K, 933 K, 1670 K, 3246 K, 4050 K, and 1460 K for graphene, Borophene, Aluminene, Germanene, BN, SiC and MoS2 respectively. Besides the analysis of temperature-energy variations, the thermal broadening is also determined and discussed to examine the thermal-stability for usage of the materials in high temperature applications.

Density functional theory based calculations were carried out to study electronic properties of transition metal elements doped into silicon carbide monolayers. The slab model SiC after doping with several 3d and 4d transition metals were analyzed to investigate the structural, electronic properties, and catalytic activity of the materials. The electronic properties of the materials after doping and adsorption were analyzed in detail in terms of density of states and band diagrams to get insights into the mechanism involved. The energy profiling was carried out by placing the mono-iodide at different possible sites on the slabs to find the favorable adsorption sites. The thorough study suggested that Zr, Nb, Mo, Cr doped SiC slabs exhibited improved catalytic activity in comparison to Pt doped SiC based CE.

Two‐dimensional (2D) materials are known to owe exceptional properties which are prerequisites for the future applications. Despite significant efforts and unprecedented achievements to realize resourceful beyond‐graphene 2D materials, the comprehensive knowledge on such materials is lacking due to which several device grade applications are still in pipeline. This work was carried out with motivation to investigate the thermal stability of contemporary 2D monolayered materials including graphene, borophene, aluminene, germanene, BN, SiC and MoS2 using Molecular Dynamics simulations. The thermal broadening, bond breakage and bond formation for the slabs are analyzed on the basis of radial distribution function (RDF). It is found that several materials out of the list are capable to withstand high temperatures depicting the essential thermal stability. The values of thermal stability of the materials were compared by plotting the temperature and energy curves whereas phase transition temperature and heat capacity of the slabs were found by taking germanene as benchmark. The phase transition temperatures are found as 4510 K, 2273 K, 933 K, 1670 K, 3246 K, 4050 K, and 1460 K for graphene, borophene, aluminene, germanene, BN, SiC, and MoS2 respectively.