Synthesis and characterization of (Sn2S3) x (Bi2S3)1-x composite thin films for solar cell applications

(Sn2S3)x(Bi2S3)1-x (x = 0, 0.2,0.5, 0.8 and 1) composite thin films have been prepared for the first time by the spray pyrolysis method on glass substrates using Tin chloride (SnCl2–H2O) and bismuth chloride (BiCl3) as precursors. The films were characterized by X-Ray diffraction (XRD), Scanning electron microscopy (SEM), optical absorption and electrical resistivity measurement techniques. XRD studies revealed that all the films contain both binary phases, i.e. Sn2S3 and Bi2S3. The band gap energy of these films varies from 1.56 to 2.01 eV. The dispersion parameters of the composite thin films were determined using e single-oscillator model. The films exhibited the lowest electrical resistivity of 5.59 × 10−2 Ω cm with an activation energy of 0.179 eV for the composition x = 0.2.