Banca de QUALIFICAÇÃO: MIZRAIM BESSA TEIXEIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MIZRAIM BESSA TEIXEIRA
DATE: 28/03/2025
TIME: 14:00
LOCAL: Plataforma Google Meet
TITLE:

Structural, optical, electronic, and mechanical properties of 2D BxCyNz-based Materials

KEY WORDS:

2D Materials, Mechanical Properties, Electronic Properties, Strain, Band Structure, DFT, Siesta.

PAGES: 117
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

Developments in nanotechnology since the synthesis of graphene have enabled the investigation of other 2D materials, with
interesting optical, electrical, and mechanical properties. Given the great diversity of potential applications, these new
materials have been intensively studied in recent years. Still, the absence of a bandgap (or a very minute one) may limit their
application in digital nanoelectronics. However, there are ways to regulate the energy between the valence and conduction
bands of a material, thus enabling a new range of applications in electronic circuits. For example, this can be accomplished by
applying strain, doping a pure carbon allotrope with atoms like boron and nitrogen, or yet using other materials as hexagonal
Boron Nitride (hBN). For other applications, such as wearable electronic device systems, the behavior of the structure under
deformation is vital, since in such systems, the material may be subjected to a degree of deformation that might compromise its
functionality. This work proposes to investigate, through Density Functional Theory (DFT) simulations, novel carbon
allotropes and BCN based 2D materials, as well as the electronic, optical and structural properties of either pure or hybrid
structures, both relaxed and under strain. Stress-strain curves were obtained from the calculations and the mechanical
properties of the chosen materials characterized. Furthermore, through band structure and Density of States (DOS)
calculations, we investigate how the gap energy varies with controlled deformation. Our results show that for 2D fullerene-
based materials, minor changes in composition can lead to considerable band gap variation, but it does not significantly affect
optical properties. They may be used to protect against high-energy UV or low-energy IR photons.

 

COMMITTEE MEMBERS:
Presidente - 2411793 - LEONARDO DANTAS MACHADO
Interno - 1354851 - MANOEL SILVA DE VASCONCELOS
Externo à Instituição - MARCELO LOPES PEREIRA JUNIOR - UnB