The role of antimony in tailoring optical properties of spray pyrolysis synthesized pbse/sb thin films for solar device optimization

Abstract

In this study, we employed the Spray Pyrolysis Technique to grow thin solid films of both Antimony-doped and undoped PbSe/Sb on glass substrates. The film growth process relied on the decomposition of lead chloride (PbCl2) and Antimony chloride in the presence of Sodium selenosulphide (Na2SeSo3). Ethylene diamine tetra acetic acid (EDTA) was utilized as a complexing agent and pH stabilizer. The determination of the films' band gaps was conducted through absorbance and transmittance measurements using a Unico-UV-2102 PC spectrophotometer, employing normal incident light in the wavelength range of 200-1500 nm. Upon annealing, thin films of undoped PbSe exhibited a higher initial absorbance of 0.70, which decreased with annealing, along with a reduced extinction coefficient from 70 to 65. Conversely, undoped PbSe displayed the highest optical conductivity, peaking at 80.4 Mmho’s at λ = 340 nm, closely followed by annealed undoped PbSe. Antimony-doped PbSe films exhibited higher reflectance, transmittance, refractive index, and real dielectric constant compared to undoped PbSe. However, they had a narrower optical band gap range of 2.2 eV, which further decreased to 2.0 eV upon annealing. Notably, doping lead selenide with antimony expanded the potential applications of the films.