A new route for the synthesis of Sn3Sb2S6 thin films by chemical deposition

In this work, SnS-Sb₂S₃ stack films were formed by sequential chemical deposition, and then they were annealed in a nitrogen atmosphere to synthesize Sn₃Sb₂S₆ thin films successfully. The structural and optical properties were studied by X-ray diffraction and transmittance and reflectance. All the samples show a high absorption coefficient of > 10⁵ cm^-1 in the visible region. Their optical bandgap and refractive index are between 1.6-1.8 eV and 3.00-2.71, respectively, which decrease with the increase of film thickness. The electrical conductivity is in the range of 10^-8 to 10^-7 Ω⁻¹ cm⁻¹. The light-generated current density (J_L) is presented as a function of Sn₃Sb₂S₆ film thickness when exposed to air mass 1.5 global (AM1.5G) and solar radiation intensity of 1000 W/m². In short, Sn₃Sb₂S₆ thin films obtained via the proposed new route exhibit appropriate properties for solar cell applications.

Keywords: sulfosalt thin films, chemical deposition, Sn3Sb2S6, thermal annealing process.