First-principles insights into the structural, mechanical, electronic, optical, and thermophysical properties of XSrBr3 (X = Na, Ga, and Tl) perovskites: Implications for optoelectronic applications

Abstract

Non-toxic halide perovskite compounds possess critical inherent and improved features for use in optoelectronic devices. The present work summarizes the physical properties of cubic halide perovskites XSrBr3 (X = Na, Ga, and Tl) based on first-principles theory. The structural, electrical, optical, mechanical, and thermophysical properties of these compounds are studied to assess their potential utility in optoelectronics field. GGA-PBE and GGA-PBEsol functionals were utilized to determine the lattice properties, cell volumes, and formation energies of the compounds. The negative formation energies support the compounds' structural stability. The compounds' bandgaps were computed using the GGA-PBE and Hybrid-HSE06 functionals. Each of the three compounds has a wide indirect bandgap. Optoelectronic devices such as UV detectors, solar panel antireflection coatings, OLED, QLED, and waveguides benefit from a greater static dielectric constant, broad absorption spectra, and low visible reflectance. The elastic stiffness constants Cij use the necessary conditions to demonstrate that the NaSrBr3, GaSrBr3, and TlSrBr3 perovskite structures are mechanically stable. The elastic modulus and other trustworthy properties imply that perovskites are mechanically ductile and soft. In conclusion, the investigation indicates the potential applications of these perovskite materials in photovoltaic and optoelectronic technologies.