Nanostructured Tin Sulfide Thin Films: Preparation via Chemical Bath Deposition and Characterization

Nanostructured tin sulfide (SnS) films were grown by chemical bath deposition (CBD) employing trisodium citrate (TSC) as complex agent. Investigation of the effect of different molar concentrations of TSC (0.10, 0.15 and 0.20 M) on the phases of  SnS was done. Structure, morphology and optical properties were studied through the use of x-ray diffraction XRD, which proves that the as-prepared SnS films orthorhombic polycrystalline structure. XRD displays that peak of maximum intensity corresponds to the preferred orientation (002) of SnS films at TSC concentration 0.20 M. The decrement of average crystalline size values was due increment of TSC content. A study of SnS morphology indicates the presence of homogeneous grains, while when concentration of TSC of 0.20 M, the grains were not homogeneous and have different sizes. The AFM image showed that the grain size was observed in the area of 72.57 nm to 60.35 nm with concentration of TSC from 0.10 M to 0.20 M respectively. The results showed excellent optical transparency. The optical transmittance reduced from 95 to 80% with increasing TSC content. The ban gap was also reduced of 1.45 to 1.25 eV with increasing TSC content. The results refer that TCS act as a  crucial role in the grown of SnS films.