Estudo de estabilidade de estruturas BxCyNz e borofenoβ12

• Autor(a) principal: Miranda, Yoshiyuki Sugawara
• Data de Publicação: 2022
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/26012
• topic: Física; DFT; BxCyNz; Borofeno; Energia de formação; Estrutura eletrônica; Physics; Borophene; Formation energy; Electronic structure; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA

The investigation of the properties of nanomaterials is essential for the application of such materials. In this study, two types of two-dimensional nanostructures were analyzed: BxCyNz structures and boropheneβ12. In this analysis, first principles calculations were used, through the Density Functional Theory (DFT), implemented by the SIESTA code. In the study of the BxCyNz structures, a comparative analysis was carried out between BCN2 and BC2N structures with geometries varying between hexagonal and 4-8, varying the type of environment between boron-rich and nitrogen-rich environments, simulating different synthesis environments. In the study of boropheneβ12, a fluorine or hydrogen adsorption process was carried out in the proportion of one atom per unit cell, varying the adsorption site. Both studies analyzed the stability of the structures according to the calculation of formation energy and their respective electronic structures. We found in the study of BxCyNz structures that the BCN2 structures within the 4-8 geometry have significantly higher gap values than the hexagonal BCN2 structures, while presenting similar stability values. The results of the analysis of the boropheneβ12 phase showed that the borophene sheets might exhibit a small gap opening depending on the adsorption site and the adsorbed element. All borophene structures calculated showed a high amount of plane perpendicular deformation (buckling) due to binding to the adsorbed atom. Despite the buckling, a relevant impact on the stability of the structures was not observed, evidencing the flexibility of borophene in terms of hybridization variations.