Comparative studies of the structural and optical properties of BiI₃ and PbI₂ iodide-based semiconductors

ABSTRACT

The structural and optical properties of BiI₃ and PbI₂ powders were compared. The x-ray diffraction results confirm that PbI₂ crystallizes in a hexagonal structure, while BiI₃ in a rhombohedral structure. The optical band gap E_g was found to be direct at (2.31 eV) for PbI₂ and indirect (1.7 eV) for BiI₃. Different fundamental optical properties such as refractive index, real and imaginary parts of optical conductivities, dielectric function, and linear susceptibility were determined. The non-linear optical properties were also discussed by deriving the linear and non-linear susceptibilities using Wemple–DiDomenico single-oscillator model. The third-order susceptibility at low absorption region was found to be equal 2.684×10⁻¹⁵ [esu] and 3.685×10⁻¹⁵ [esu], as well as the non-linear refractive index n_2, 7.5×10⁻¹⁴ [esu] and 1.07×10⁻¹³ [esu] for BiI₃ and PbI₂ respectively, which evidences their interest in optoelectronic devices.

KEYWORDS:

• Iodide
• UV-Visible spectroscopy
• optical properties
• optoelectronic devices

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

The research was supported by the Tunisio-Marrocain 20/R&D23 project.