Hydrogen and fluorine substituted graphyne and graphdiyne sheets: Exploration of electronic and optical properties using density functional theory

Abstract

This study delves into the geometrical structure, electronic characteristics, and optical properties of hydrogen (H) and fluorine (F) substituted graphyne (GY) and graphdiyne (GDY) sheets using density functional theory (DFT). The investigated sheets are denoted as R-GY and R-GDY, where R represents either H or F. Our results reveal the energetic stability of these sheets through cohesive energy calculations and confirm their thermal stability via ab-initio molecular dynamics (AIMD) simulations. It is found that R-GY and R-GDY sheets are semiconductors. The optical characteristics of H-substituted sheets closely resemble those of F-substituted ones. The findings showcase the strong light-absorbing capabilities of R-GY and R-GDY sheets in the visible and ultraviolet regions, making them favorable materials for applications in photovoltaic systems and ultraviolet absorbers. The reflection and transmission coefficients indicate the high transparency of the sheets for light. Our findings could enhance the understanding of the electronic and optical properties of R-GY and R-GDY, potentially inspiring researchers to develop optoelectronic devices utilizing these materials.